chore: remove outdated examples

All of the examples were out of date and we do not have a mechanism for
keeping them up to date. Removed the examples.

.github/workflows/close-stale-issues.yml

@@ -15,7 +15,7 @@ jobs:
     runs-on: ubuntu-latest
     name: Stale issue job
     steps:
-    - uses: aws-actions/stale-issue-cleanup@v6
+    - uses: aws-actions/stale-issue-cleanup@v7
       with:
         # Setting messages to an empty string will cause the automation to skip
         # that category

.github/workflows/release-please.yml

@@ -55,6 +55,8 @@
           run: |
             git config user.name "GitHub Actions"
             git config user.email "github-aws-sdk-osds-automation@amazon.com"
+            echo "::add-mask::${{ env.OSDS_ACCESS_TOKEN }}"
+            git remote set-url origin https://${{ env.OSDS_ACCESS_TOKEN }}@github.com/aws-actions/configure-aws-credentials.git
             if git rev-parse "v${{ steps.release.outputs.major }}" >/dev/null 2>&1; then
               git tag -d "v${{ steps.release.outputs.major }}"
               git push origin ":v${{ steps.release.outputs.major }}"

.release-please-manifest.json

@@ -1,5 +1,5 @@
 {
   ".release-please-manifest.json": "4.0.2",
   "package.json": "6.0.0",
-  ".": "6.2.2"
+  ".": "6.2.3"
 }

CHANGELOG.md

@@ -2,6 +2,14 @@
 
 All notable changes to this project will be documented in this file. See [standard-version](https://github.com/conventional-changelog/standard-version) for commit guidelines.
 
+## [6.2.3](https://github.com/aws-actions/configure-aws-credentials/compare/v6.2.2...v6.2.3) (2026-07-22)
+
+
+### Bug Fixes
+
+* attach git credentials before Tag Major Version push ([#1877](https://github.com/aws-actions/configure-aws-credentials/issues/1877)) ([9ae780b](https://github.com/aws-actions/configure-aws-credentials/commit/9ae780b171afa8c5a3a6a2d154a765b709492482))
+* PackedPolicyTooLarge detection in STS tags ([#1899](https://github.com/aws-actions/configure-aws-credentials/issues/1899)) ([fa8d6a5](https://github.com/aws-actions/configure-aws-credentials/commit/fa8d6a57bbf44b34439fb080bbdadc7c92c285eb))
+
 ## [6.2.2](https://github.com/aws-actions/configure-aws-credentials/compare/v6.2.1...v6.2.2) (2026-07-07)
 
 

CONTRIBUTING.md

@@ -28,6 +28,12 @@ these are incredibly useful:
 - Any modifications you've made relevant to the bug
 - Anything unusual about your environment or deployment
 
+We also ask that you refrain from opening issues via the `gh` CLI or GitHub
+API. These methods bypass our issue templates and therefore don't apply the
+proper labels or workflows that we use. Note that AI agents typically do not
+properly use issue templates. Issues that don't have the proper labels
+applied may be closed without comment.
+
 ## Contributing via Pull Requests
 
 Contributions via pull requests are much appreciated. Before sending us a pull

README.md

@@ -26,7 +26,7 @@ Authenticate to AWS in GitHub Actions (and others)! Works especially well with
          "Condition": {
            "StringEquals": {
              "token.actions.githubusercontent.com:aud": "sts.amazonaws.com",
-             "token.actions.githubusercontent.com:sub": "repo:<GITHUB_ORG>/<GITHUB_REPOSITORY>:ref:refs/heads/<GITHUB_BRANCH>"
+             "token.actions.githubusercontent.com:sub": "repo:<GITHUB_ORG>@<ORG_ID>/<GITHUB_REPOSITORY>@<REPO_ID>:ref:refs/heads/<GITHUB_BRANCH>"
            }
          }
        }
@@ -36,11 +36,16 @@ Authenticate to AWS in GitHub Actions (and others)! Works especially well with
 
    </details>
 
-   Note: if you are running in a GitHub environment based workflow, the value
+   Note: The value of the `sub` claim may be different depending on the workflow
-   for the Sub claim will be different, in the form of
+   and the environment in which it's running. Workflows in repositories created
-   `repo:<GITHUB_ORG>/<GITHUB_REPOSITORY>:environment:<ENVIRONMENT_NAME>`.
+   prior to [15 July 2026][immutable-sub] will omit the `@<ORG_ID>` and
-   Adjust the trust policy accordingly if you are using environment-based
+   `@<REPO_ID>` suffixes unless opted in. Workflows running in GitHub
-   workflows.
+   environments will include an`environment:<ENVIRONMENT_NAME>` stanza.  See
+   [Claims and scoping permissions](#claims-and-scoping-permissions) for more
+   information.
+
+   [immutable-sub]:
+   https://github.blog/changelog/2026-04-23-immutable-subject-claims-for-github-actions-oidc-tokens/
 
 3. Attach permissions to the IAM Role that allow it to access the AWS resources
    you need.
@@ -56,7 +61,7 @@ Authenticate to AWS in GitHub Actions (and others)! Works especially well with
        runs-on: ubuntu-latest
        steps:
          - name: Configure AWS Credentials
-           uses: aws-actions/configure-aws-credentials@v6.1.0
+           uses: aws-actions/configure-aws-credentials@v6.2.3
            with:
              role-to-assume: <Role ARN you created in step 2>
              aws-region: <AWS Region you want to use>
@@ -245,7 +250,7 @@ specify the profile name as an environment variable in the job step:
 
 ```yaml
 - name: Configure AWS Credentials
-  uses: aws-actions/configure-aws-credentials@v6.1.0
+  uses: aws-actions/configure-aws-credentials@v6.2.3
   with:
     aws-region: us-east-1
     role-to-assume: arn:aws:iam::123456789100:role/my-role
@@ -263,14 +268,14 @@ step environment variables:
 
 ```yaml
 - name: Configure AWS credentials
-  uses: aws-actions/configure-aws-credentials@v6.1.0
+  uses: aws-actions/configure-aws-credentials@v6.2.3
   with:
     aws-region: us-east-1
     role-to-assume: arn:aws:iam::123456789100:role/my-first-role
     aws-profile: firstRoleInChain
 
 - name: assume second role
-  uses: aws-actions/configure-aws-credentials@v6.1.0
+  uses: aws-actions/configure-aws-credentials@v6.2.3
   with:
     aws-region: us-east-2
     role-to-assume: arn:aws:iam::987654321000:role/my-second-role
@@ -306,7 +311,7 @@ this action will always consider the `HTTP_PROXY` environment variable.
 Manually configured proxy:
 
 ```yaml
-uses: aws-actions/configure-aws-credentials@v6.1.0
+uses: aws-actions/configure-aws-credentials@v6.2.3
 with:
   aws-region: us-east-2
   role-to-assume: my-github-actions-role
@@ -453,7 +458,7 @@ line.
 <summary>Inline session policy examples</summary>
 
 ```yaml
-uses: aws-actions/configure-aws-credentials@v6.1.0
+uses: aws-actions/configure-aws-credentials@v6.2.3
 with:
   inline-session-policy: '{"Version":"2012-10-17","Statement":[{"Sid":"Stmt1","Effect":"Allow","Action":"s3:List*","Resource":"*"}]}'
 ```
@@ -461,7 +466,7 @@ with:
 Or we can have a nicely formatted JSON as well:
 
 ```yaml
-uses: aws-actions/configure-aws-credentials@v6.1.0
+uses: aws-actions/configure-aws-credentials@v6.2.3
 with:
   inline-session-policy: >-
     {
@@ -489,7 +494,7 @@ the role.
 <summary>Managed session policy examples</summary>
 
 ```yaml
-uses: aws-actions/configure-aws-credentials@v6.1.0
+uses: aws-actions/configure-aws-credentials@v6.2.3
 with:
   managed-session-policies: arn:aws:iam::aws:policy/AmazonS3ReadOnlyAccess
 ```
@@ -497,7 +502,7 @@ with:
 And we can pass multiple managed policies likes this:
 
 ```yaml
-uses: aws-actions/configure-aws-credentials@v6.1.0
+uses: aws-actions/configure-aws-credentials@v6.2.3
 with:
   managed-session-policies: |
     arn:aws:iam::aws:policy/AmazonS3ReadOnlyAccess
@@ -543,7 +548,7 @@ specify the audience through the `audience` input:
 
 ```yaml
 - name: Configure AWS Credentials for China region audience
-  uses: aws-actions/configure-aws-credentials@v6.1.0
+  uses: aws-actions/configure-aws-credentials@v6.2.3
   with:
     audience: sts.amazonaws.com.cn
     aws-region: cn-northwest-1
@@ -593,6 +598,30 @@ claims ([1][gh-blog-oidc], [2][sub-claim-custom]).
 > unintended access. Instead, use `StringEquals` or `StringLike` operators to
 > check for specific claim values.
 
+#### Immutable subject claims
+
+Repositories created on github.com on or after 15 July 2026, older
+repositories that have opted in, and older repositories that have been renamed
+since 15 July 2026, emit an [immutable `sub` claim][immutable-sub].
+This claim appends the permanent numeric ID of the organization and of the
+repository after each name, separated by `@`, so that a recycled org or
+repository name cannot be used to mint tokens matching a stale trust policy.
+For example:
+
+```text
+# Legacy (mutable) sub claim
+repo:octo-org/octo-repo:ref:refs/heads/main
+
+# Immutable sub claim
+repo:octo-org@123456/octo-repo@789012:ref:refs/heads/main
+```
+
+If your trust policy matches the legacy name-only form and your repository emits
+the immutable claim, `AssumeRoleWithWebIdentity` fails with `Not authorized to
+perform sts:AssumeRoleWithWebIdentity`. To fix this, update the `sub` condition
+to the immutable form. You can find your repository's prefix in the Settings,
+or by following the token inspection steps below.
+
 [least-privilege]:
   https://docs.aws.amazon.com/IAM/latest/UserGuide/best-practices.html#grant-least-privilege
 [gh-blog-oidc]:
@@ -605,7 +634,7 @@ claims ([1][gh-blog-oidc], [2][sub-claim-custom]).
 If you aren't sure what claim values your workflow is producing, the
 [`actions-oidc-debugger`](https://github.com/github/actions-oidc-debugger)
 action will print the decoded JWT payload. Run it in a private repository
-only — the token itself is short-lived but the claim values may be sensitive.
+only; the token itself is short-lived but the claim values may be sensitive.
 
 See the GitHub [security-hardening guide][gh-oidc-hardening] for further
 discussion of trust conditions and threat modeling.
@@ -680,7 +709,7 @@ Provider. The audience would still be `sts.amazonaws.com` by default.
 
 ```yaml
 - name: Configure AWS Credentials
-  uses: aws-actions/configure-aws-credentials@v6.1.0
+  uses: aws-actions/configure-aws-credentials@v6.2.3
   with:
     aws-region: us-east-2
     role-to-assume: arn:aws:iam::123456789100:role/my-github-actions-role
@@ -696,13 +725,13 @@ environment variable and use it to assume the role
 
 ```yaml
 - name: Configure AWS Credentials
-  uses: aws-actions/configure-aws-credentials@v6.1.0
+  uses: aws-actions/configure-aws-credentials@v6.2.3
   with:
     aws-region: us-east-2
     role-to-assume: arn:aws:iam::123456789100:role/my-github-actions-role
     role-session-name: MySessionName
 - name: Configure other AWS Credentials
-  uses: aws-actions/configure-aws-credentials@v6.1.0
+  uses: aws-actions/configure-aws-credentials@v6.2.3
   with:
     aws-region: us-east-2
     role-to-assume: arn:aws:iam::987654321000:role/my-second-role
@@ -724,7 +753,7 @@ alternatively, the `TagSession` permission can be omitted if you are using the
 
 ```yaml
 - name: Configure AWS Credentials
-  uses: aws-actions/configure-aws-credentials@v6.1.0
+  uses: aws-actions/configure-aws-credentials@v6.2.3
   with:
     aws-access-key-id: ${{ secrets.AWS_ACCESS_KEY_ID }}
     aws-secret-access-key: ${{ secrets.AWS_SECRET_ACCESS_KEY }}
@@ -745,7 +774,7 @@ like `role-to-assume: my-github-actions-role`.
 ```yaml
 - name: Configure AWS Credentials 1
   id: creds
-  uses: aws-actions/configure-aws-credentials@v6.1.0
+  uses: aws-actions/configure-aws-credentials@v6.2.3
   with:
     aws-region: us-east-2
     role-to-assume: arn:aws:iam::123456789100:role/my-github-actions-role
@@ -754,7 +783,7 @@ like `role-to-assume: my-github-actions-role`.
   run: |
     aws sts get-caller-identity
 - name: Configure AWS Credentials 2
-  uses: aws-actions/configure-aws-credentials@v6.1.0
+  uses: aws-actions/configure-aws-credentials@v6.2.3
   with:
     aws-region: us-east-2
     aws-access-key-id: ${{ steps.creds.outputs.aws-access-key-id }}
@@ -785,14 +814,14 @@ provided.
 
 ```yaml
 - name: Configure AWS Credentials for Dev
-  uses: aws-actions/configure-aws-credentials@v6.1.0
+  uses: aws-actions/configure-aws-credentials@v6.2.3
   with:
     aws-region: us-east-1
     role-to-assume: arn:aws:iam::111111111111:role/dev-role
     aws-profile: dev
 
 - name: Configure AWS Credentials for Prod
-  uses: aws-actions/configure-aws-credentials@v6.1.0
+  uses: aws-actions/configure-aws-credentials@v6.2.3
   with:
     aws-region: us-west-2
     role-to-assume: arn:aws:iam::222222222222:role/prod-role

THIRD-PARTY

@@ -222,7 +222,7 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 The following npm package may be included in this product:
 
- - @aws-sdk/client-sts@3.1080.0
+ - @aws-sdk/client-sts@3.1116.0
 
 This package contains the following license:
 
@@ -432,9 +432,9 @@ Apache License
 
 The following npm packages may be included in this product:
 
- - @aws-sdk/signature-v4-multi-region@3.996.38
+ - @aws-sdk/signature-v4-multi-region@3.996.46
- - @smithy/core@3.29.1
+ - @smithy/core@3.33.3
- - @smithy/types@4.15.1
+ - @smithy/types@4.17.2
 
 These packages each contain the following license:
 
@@ -832,7 +832,7 @@ SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 The following npm package may be included in this product:
 
- - @aws-sdk/core@3.974.28
+ - @aws-sdk/core@3.977.9
 
 This package contains the following license:
 
@@ -1042,16 +1042,16 @@ Apache License
 
 The following npm packages may be included in this product:
 
- - @aws-sdk/credential-provider-env@3.972.54
+ - @aws-sdk/credential-provider-env@3.972.70
- - @aws-sdk/credential-provider-ini@3.972.61
+ - @aws-sdk/credential-provider-ini@3.973.15
- - @aws-sdk/credential-provider-node@3.972.63
+ - @aws-sdk/credential-provider-node@3.972.81
- - @aws-sdk/token-providers@3.1080.0
+ - @aws-sdk/token-providers@3.1116.0
- - @aws-sdk/types@3.973.15
+ - @aws-sdk/types@3.974.5
- - @aws-sdk/xml-builder@3.972.33
+ - @aws-sdk/xml-builder@3.972.40
- - @smithy/credential-provider-imds@4.4.6
+ - @smithy/credential-provider-imds@4.5.2
- - @smithy/fetch-http-handler@5.6.3
+ - @smithy/fetch-http-handler@5.7.2
- - @smithy/node-http-handler@4.9.3
+ - @smithy/node-http-handler@4.11.3
- - @smithy/signature-v4@5.6.2
+ - @smithy/signature-v4@5.6.12
 
 These packages each contain the following license:
 
@@ -1261,9 +1261,9 @@ Apache License
 
 The following npm packages may be included in this product:
 
- - @aws-sdk/credential-provider-process@3.972.54
+ - @aws-sdk/credential-provider-process@3.972.70
- - @aws-sdk/credential-provider-sso@3.972.60
+ - @aws-sdk/credential-provider-sso@3.973.14
- - @aws-sdk/credential-provider-web-identity@3.972.60
+ - @aws-sdk/credential-provider-web-identity@3.972.76
 
 These packages each contain the following license:
 
@@ -1473,9 +1473,9 @@ Apache License
 
 The following npm packages may be included in this product:
 
- - @aws-sdk/credential-provider-http@3.972.56
+ - @aws-sdk/credential-provider-http@3.972.72
- - @aws-sdk/credential-provider-login@3.972.60
+ - @aws-sdk/credential-provider-login@3.972.77
- - @aws-sdk/nested-clients@3.997.28
+ - @aws-sdk/nested-clients@3.997.44
 
 These packages each contain the following license:
 
@@ -1485,7 +1485,7 @@ Apache-2.0
 
 The following npm package may be included in this product:
 
- - ip-address@10.2.0
+ - ip-address@10.4.0
 
 This package contains the following license:
 
@@ -1740,7 +1740,7 @@ SOFTWARE.
 
 The following npm package may be included in this product:
 
- - undici@6.27.0
+ - undici@6.28.0
 
 This package contains the following license:
 

dist/cleanup/index.js

@@ -1929,7 +1929,11 @@ var require_request = __commonJS({
           } else if (typeof val[i] === "object") {
             throw new InvalidArgumentError(`invalid ${key} header`);
           } else {
-            arr.push(`${val[i]}`);
+            const str = `${val[i]}`;
+            if (!isValidHeaderValue(str)) {
+              throw new InvalidArgumentError(`invalid ${key} header`);
+            }
+            arr.push(str);
           }
         }
         val = arr;
@@ -1941,6 +1945,9 @@ var require_request = __commonJS({
         val = "";
       } else {
         val = `${val}`;
+        if (!isValidHeaderValue(val)) {
+          throw new InvalidArgumentError(`invalid ${key} header`);
+        }
       }
       if (headerName === "host") {
         if (request.host !== null) {
@@ -5671,6 +5678,7 @@ var require_client_h1 = __commonJS({
       RequestContentLengthMismatchError,
       ResponseContentLengthMismatchError,
       RequestAbortedError,
+      InvalidArgumentError,
       HeadersTimeoutError,
       HeadersOverflowError,
       SocketError,
@@ -6397,8 +6405,16 @@ var require_client_h1 = __commonJS({
         }
         body = bodyStream.stream;
         contentLength = bodyStream.length;
-      } else if (util.isBlobLike(body) && request.contentType == null && body.type) {
+      } else if (util.isBlobLike(body) && request.contentType == null) {
-        headers.push("content-type", body.type);
+        const contentType = body.type;
+        if (contentType) {
+          const contentTypeValue = `${contentType}`;
+          if (!util.isValidHeaderValue(contentTypeValue)) {
+            util.errorRequest(client, request, new InvalidArgumentError("invalid content-type header"));
+            return false;
+          }
+          headers.push("content-type", contentTypeValue);
+        }
       }
       if (body && typeof body.read === "function") {
         body.read(0);
@@ -8950,6 +8966,24 @@ var require_retry_handler = __commonJS({
       const current = Date.now();
       return new Date(retryAfter).getTime() - current;
     }
+    function validatePartialResponseContentLength(headers, range, statusCode, retryCount) {
+      const contentLength = headers["content-length"];
+      if (contentLength == null) {
+        return null;
+      }
+      if (!Number.isFinite(range.start) || !Number.isFinite(range.end)) {
+        return null;
+      }
+      const length = Number(contentLength);
+      const expectedLength = range.end - range.start + 1;
+      if (!Number.isFinite(length) || length !== expectedLength) {
+        return new RequestRetryError("Content-Length mismatch", statusCode, {
+          headers,
+          data: { count: retryCount }
+        });
+      }
+      return null;
+    }
     var RetryHandler = class _RetryHandler {
       constructor(opts, handlers) {
         const { retryOptions, ...dispatchOpts } = opts;
@@ -9122,6 +9156,11 @@ var require_retry_handler = __commonJS({
             );
             return false;
           }
+          const contentLengthError = validatePartialResponseContentLength(headers, contentRange, statusCode, this.retryCount);
+          if (contentLengthError != null) {
+            this.abort(contentLengthError);
+            return false;
+          }
           const { start, size, end = size - 1 } = contentRange;
           assert(this.start === start, "content-range mismatch");
           assert(this.end == null || this.end === end, "content-range mismatch");
@@ -9139,6 +9178,11 @@ var require_retry_handler = __commonJS({
                 statusMessage
               );
             }
+            const contentLengthError = validatePartialResponseContentLength(headers, range, statusCode, this.retryCount);
+            if (contentLengthError != null) {
+              this.abort(contentLengthError);
+              return false;
+            }
             const { start, size, end = size - 1 } = range;
             assert(
               start != null && Number.isFinite(start),
@@ -15984,14 +16028,48 @@ var require_util6 = __commonJS({
       for (let i = 0; i < path.length; ++i) {
         const code = path.charCodeAt(i);
         if (code < 32 || // exclude CTLs (0-31)
-        code === 127 || // DEL
+        code > 126 || // exclude DEL and non-ascii
         code === 59) {
           throw new Error("Invalid cookie path");
         }
       }
     }
+    function isLetterOrDigit(code) {
+      return code >= 48 && code <= 57 || // 0-9
+      code >= 65 && code <= 90 || // A-Z
+      code >= 97 && code <= 122;
+    }
     function validateCookieDomain(domain) {
-      if (domain.startsWith("-") || domain.endsWith(".") || domain.endsWith("-")) {
+      if (domain === " ") {
+        return;
+      }
+      if (domain.length > 255) {
+        throw new Error("Invalid cookie domain");
+      }
+      let labelLength = 0;
+      for (let i = 0; i < domain.length; ++i) {
+        const code = domain.charCodeAt(i);
+        if (code === 46) {
+          if (labelLength === 0) {
+            throw new Error("Invalid cookie domain");
+          }
+          if (domain.charCodeAt(i - 1) === 45) {
+            throw new Error("Invalid cookie domain");
+          }
+          labelLength = 0;
+          continue;
+        }
+        if (labelLength === 0 && !isLetterOrDigit(code)) {
+          throw new Error("Invalid cookie domain");
+        }
+        if (!isLetterOrDigit(code) && code !== 45) {
+          throw new Error("Invalid cookie domain");
+        }
+        if (++labelLength > 63) {
+          throw new Error("Invalid cookie domain");
+        }
+      }
+      if (labelLength === 0 || domain.charCodeAt(domain.length - 1) === 45) {
         throw new Error("Invalid cookie domain");
       }
     }
@@ -16074,7 +16152,11 @@ var require_util6 = __commonJS({
           throw new Error("Invalid unparsed");
         }
         const [key, ...value] = part.split("=");
-        out.push(`${key.trim()}=${value.join("=")}`);
+        const trimmedKey = key.trim();
+        const joinedValue = value.join("=");
+        validateCookieName(trimmedKey);
+        validateCookieValue(joinedValue);
+        out.push(`${trimmedKey}=${joinedValue}`);
       }
       return out.join("; ");
     }

examples/README.md

@@ -1,14 +0,0 @@
-# Examples
-
-## [federated-setup](./federated-setup/README.md)
-
-The directory contains templates for setting up the `configure-aws-credentials`
-federation between your GitHub Organization/repository and your AWS account.
-
-## [cfn-deploy-example](./cfn-deploy-example/README.md)
-
-Repository example uses aws-action `configure-aws-credentials` with OIDC
-federation template
-[github-actions-oidc-federation-and-role](./github-actions-oidc-federation-and-role.yml).
-Example demonstrates a repository that deploys AWS CloudFormation template using
-cfn-deploy GitHub Action.

examples/cfn-deploy-example/.github/workflows/compliance.yml

@@ -1,15 +0,0 @@
-name: 'compliance'
-## run ci testing on all push events
-on: [push]
-jobs:
-  ## Guard rule set
-  sast-guard:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v5
-    - uses: grolston/guard-action@main
-      with:
-        data_directory: './cloudformation/' ## change to your template directory
-        rule_set: 'FedRAMP-Moderate'
-        show_summary: 'all'
-        output_format: 'single-line-summary'

examples/cfn-deploy-example/.github/workflows/deploy.yml

@@ -1,38 +0,0 @@
----
-name: deploy
-on:
-  push:
-    branches:
-      - main
-env:
-  AWS_DEFAULT_REGION: us-east-1
-  AWS_DEFAULT_OUTPUT: json
-
-jobs:
-  deploy-cfn:
-    name: deploy
-    runs-on: ubuntu-latest
-    # These permissions are needed to interact with GitHub’s OIDC Token endpoint.
-    permissions:
-      id-token: write
-      contents: read
-    steps:
-    - name: Checkout
-      uses: actions/checkout@v5
-    - name: Configure AWS Credentials
-      uses: aws-actions/configure-aws-credentials@v6
-      with:
-        aws-region: us-east-1
-        ## the following creates an ARN based on the values entered into github secrets
-        role-to-assume: arn:aws:iam::${{ secrets.AWS_ACCOUNT_ID }}:role/${{ secrets.AWS_DEPLOY_ROLE }}
-        role-session-name: myGitHubActions
-    - name: Deploy EC2 Bastion
-      uses: aws-actions/aws-cloudformation-github-deploy@v1.3.0
-      with:
-        name: myEC2bastion
-        ## change to path to template in your github repo
-        template: cloudformation/ec2-bastion.yml
-        capabilities: CAPABILITY_IAM, CAPABILITY_NAMED_IAM
-        no-fail-on-empty-changeset: "1"
-        ## parameter set in github secrets
-        parameter-overrides: "pVpc=${{ secrets.VPC_ID }},pSubnet=${{ secrets.SUBNET_ID }}"

examples/cfn-deploy-example/README.md

@@ -1,24 +0,0 @@
-# cfn-deploy example
-
-Example uses aws-action `configure-aws-credentials` with OIDC federation. Prior
-to using this example project, the user needs to deploy the
-[github-actions-oidc-federation-and-role](../federated-setup/github-actions-oidc-federation-and-role.yml)
-template in the AWS account they want to deploy the CloudFormation template
-into. Specify the GitHub Organization name, repository name, and the specific
-branch you want to deploy on.
-
-Within the [github/workflows](./.github/workflows/) directory there is a
-[compliance.yml](./.github/workflows/compliance.yml) and a
-[deploy.yml](./.github/workflows/deploy.yml). The deploy.yml file leverages the
-aws-action `configure-aws-credentials` and accesses GitHub Action Secrets for
-some of the variables. The compliance.yml runs static application security
-testing using cfn-guard.
-
-To use the example you will need to set the following GitHub Action Secrets:
-
-| Secret Key      | Used With                        | Description                              |
-| --------------- | -------------------------------- | ---------------------------------------- |
-| AWS_ACCOUNT_ID  | configure-aws-credentials        | The AWS account ID                       |
-| AWS_DEPLOY_ROLE | configure-aws-credentials        | The name of the IAM role                 |
-| VPC_ID          | aws-cloudformation-github-deploy | VPC ID the EC2 Bastion is deployed to    |
-| SUBNET_ID       | aws-cloudformation-github-deploy | Subnet ID the EC2 Bastion is deployed to |

examples/cfn-deploy-example/ec2-bastion.yml

@@ -1,150 +0,0 @@
----
-AWSTemplateFormatVersion: "2010-09-09"
-Description: EC2 bastion for latest AWS Linux 2 EC2 deployment
-Metadata:
-  AWS::CloudFormation::Interface:
-    ParameterGroups:
-      - Label:
-          default: "EC2 Configuration"
-        Parameters:
-          - pTagNameValue
-          - pOperatingSystem
-          - pInstanceType
-          - pVolumeSize
-          - pEbsDeleteOnTermination
-      - Label:
-          default: "Network Configuration"
-        Parameters:
-          - pVpc
-          - pSubnet
-    ParameterLabels:
-      pOperatingSystem:
-        default: "Operating System"
-      pInstanceType:
-        default: "Instance Type"
-      pTagNameValue:
-        default: "EC2 Name"
-      pVolumeSize:
-        default: "Volume Size"
-      pEbsDeleteOnTermination:
-        default: "Delete EBS Volume on Termination"
-      pSubnet:
-        default: "Subnet"
-      pVpc:
-        default: "VPC"
-Parameters:
-  pSubnet:
-    Description: The subnet to launch the instance in to. It must be part of the VPC chosen above.
-    Type: AWS::EC2::Subnet::Id
-  pVpc:
-    Description: The VPC to launch the EC2 instance in to.
-    Type: AWS::EC2::VPC::Id
-  pOperatingSystem:
-    Type: "AWS::SSM::Parameter::Value<AWS::EC2::Image::Id>"
-    Default: "/aws/service/ami-amazon-linux-latest/amzn2-ami-hvm-x86_64-ebs"
-  pInstanceType:
-    Description: Desired Instance Size
-    Type: String
-    Default: t3.small
-    AllowedValues:
-      - t3.small
-      - t3.medium
-      - t3.nano
-  pTagNameValue:
-    Description: "Required: Enter the tag name you'd like applied to the instance. Tag Name gives the name to the EC2 instance."
-    Type: String
-    MinLength: 1
-    Default: "myBastion"
-  pVolumeSize:
-    Description:
-      Enter the number of GBs you want your volume to be. The minimum value
-      is 8 GBs
-    Type: Number
-    Default: 50
-    MinValue: 8
-  pEbsDeleteOnTermination:
-    Description: "Specify if the EBS volume should be deleted if EC2 is deleted."
-    Type: String
-    Default: true
-    AllowedValues:
-      - true
-      - false
-Rules:
-  SubnetInVPC:
-    Assertions:
-      - Assert: !EachMemberIn
-          - !ValueOfAll
-            - AWS::EC2::Subnet::Id
-            - VpcId
-          - !RefAll "AWS::EC2::VPC::Id"
-        AssertDescription: All subnets must in the VPC
-Resources:
-  rSecurityGroupDefault:
-    Type: AWS::EC2::SecurityGroup
-    Properties:
-      GroupDescription: !Sub "Default SG for SC Product ${pTagNameValue} "
-      VpcId: !Ref pVpc
-      SecurityGroupEgress:
-        - Description: Outbound unrestricted traffic
-          IpProtocol: "-1"
-          CidrIp: 0.0.0.0/0
-      Tags:
-        - Key: Name
-          Value: !Ref pTagNameValue
-  rLinuxEc2:
-    Type: AWS::EC2::Instance
-    Metadata:
-      guard:
-        SuppressedRules:
-          - 'EC2_INSTANCE_DETAILED_MONITORING_ENABLED'
-    Properties:
-      ImageId: !Ref pOperatingSystem
-      IamInstanceProfile: !Ref rec2InstanceProfile
-      Monitoring: false
-      InstanceType: !Ref pInstanceType
-      EbsOptimized: true
-      SourceDestCheck: true
-      SubnetId: !Ref pSubnet
-      SecurityGroupIds:
-        - !Ref rSecurityGroupDefault
-      BlockDeviceMappings:
-        - DeviceName: "/dev/xvda"
-          Ebs:
-            VolumeSize: !Ref pVolumeSize
-            DeleteOnTermination: !Ref pEbsDeleteOnTermination
-      Tags:
-        - Key: Name
-          Value: !Ref pTagNameValue
-      UserData:
-        Fn::Base64:
-          yum update -y
-  ## Instance Profiles
-  ## EC2 IAM Roles
-  rEc2Role:
-    Type: AWS::IAM::Role
-    Properties:
-      RoleName:  !Sub "ec2-role-${AWS::StackName}"
-      AssumeRolePolicyDocument:
-        Statement:
-          - Effect: Allow
-            Principal:
-              Service: [ec2.amazonaws.com]
-            Action: ['sts:AssumeRole']
-      Path: /
-      ManagedPolicyArns:
-      - !Sub 'arn:${AWS::Partition}:iam::aws:policy/AmazonSSMManagedInstanceCore'
-      - !Sub 'arn:${AWS::Partition}:iam::aws:policy/CloudWatchAgentServerPolicy'
-  rec2InstanceProfile:
-    Type: AWS::IAM::InstanceProfile
-    Properties:
-      InstanceProfileName: !Sub "ec2-profile-${AWS::StackName}"
-      Path: /
-      Roles:
-        - !Ref rEc2Role
-Outputs:
-  oLinuxEc2InstanceId:
-    Description: Resource ID of the newly created EC2 instance
-    Value: !Ref rLinuxEc2
-  oLinuxEc2PrivateIP:
-    Description: Private IP Address for EC2
-    Value: !GetAtt rLinuxEc2.PrivateIp

examples/federated-setup/README.md

@@ -1,11 +0,0 @@
-# federated-setup
-
-## [github-action-oidc-federation](./github-actions-oidc-federation.yml)
-
-Setup of the OIDC federation between your GitHub Organization/repository and
-your AWS account.
-
-## [github-actions-oidc-federation-and-role](./github-actions-oidc-federation-and-role.yml)
-
-Setup of the OIDC federation between your GitHub Organization/repository and
-your AWS account along with a role that only executes on specific branch.

examples/federated-setup/github-actions-oidc-federation-and-role.yml

@@ -1,82 +0,0 @@
----
-AWSTemplateFormatVersion: "2010-09-09"
-Description: Github Actions configuration - OIDC IAM IdP and associated role CI/CD
-
-Parameters:
-
-  GitHubOrganization:
-    Type: String
-    Description: This is the root organization or personal account where repos are stored (Case Sensitive)
-
-  RepositoryName:
-    Type: String
-    Description: The repo(s) these roles will have access to. (Use * for all org or personal repos)
-    Default: "*"
-
-  BranchName:
-    Type: String
-    Description: Name of the git branch to to trust. (Use * for all branches)
-    Default: "*"
-
-  RoleName:
-    Type: String
-    Description: Name the Role
-
-  UseExistingProvider:
-    Type: String
-    Description: "Only one GitHub Provider can exists. Choose yes if one is already present in account"
-    Default: "no"
-    AllowedValues:
-      - "yes"
-      - "no"
-
-Conditions:
-
-  CreateProvider: !Equals ["no", !Ref UseExistingProvider]
-
-Resources:
-
-  IdpGitHubOidc:
-    Type: AWS::IAM::OIDCProvider
-    Condition: CreateProvider
-    Properties:
-      Url: https://token.actions.githubusercontent.com
-      ClientIdList:
-        - sts.amazonaws.com
-        - !Sub https://github.com/${GitHubOrganization}/${RepositoryName}
-      ThumbprintList:
-        - 6938fd4d98bab03faadb97b34396831e3780aea1
-      Tags:
-        - Key: Name
-          Value: !Sub ${RoleName}-OIDC-Provider
-
-  RoleGithubActions:
-    Type: AWS::IAM::Role
-    Properties:
-      RoleName: !Ref RoleName
-      AssumeRolePolicyDocument:
-        Statement:
-          - Effect: Allow
-            Action: sts:AssumeRoleWithWebIdentity
-            Principal:
-              Federated: !If
-                - CreateProvider
-                - !Ref IdpGitHubOidc
-                - !Sub arn:${AWS::Partition}:iam::${AWS::AccountId}:oidc-provider/token.actions.githubusercontent.com
-            Condition:
-              StringLike:
-                token.actions.githubusercontent.com:sub: !Sub repo:${GitHubOrganization}/${RepositoryName}:ref:refs/heads/${BranchName}
-      ManagedPolicyArns:
-        ## edit the managed policy to give least privileges
-        - !Sub arn:${AWS::Partition}:iam::aws:policy/AdministratorAccess
-
-Outputs:
-
-  IdpGitHubOidc:
-    Condition: CreateProvider
-    Description: "ARN of Github OIDC Provider"
-    Value: !GetAtt IdpGitHubOidc.Arn
-
-  RoleGithubActionsARN:
-    Description: "CICD Role for GitHub Actions"
-    Value: !GetAtt RoleGithubActions.Arn

examples/federated-setup/github-actions-oidc-federation.yml

@@ -1,43 +0,0 @@
----
-AWSTemplateFormatVersion: "2010-09-09"
-Description: Github Actions configuration - OIDC IAM IdP Federation
-
-Parameters:
-
-  GitHubOrganization:
-    Type: String
-    Description: This is the root organization or personal account where repos are stored (Case Sensitive)
-    Default: ""
-
-  RepositoryName:
-    Type: String
-    Description: The repo(s) these roles will have access to. (Use * for all org or personal repos)
-    Default: "*"
-
-  RoleName:
-    Type: String
-    Description: Name the Role
-    Default: ""
-
-
-Resources:
-
-  IdpGitHubOidc:
-    Type: AWS::IAM::OIDCProvider
-    Properties:
-      Url: https://token.actions.githubusercontent.com
-      ClientIdList:
-        - sts.amazonaws.com
-        - !Sub https://github.com/${GitHubOrganization}/${RepositoryName}
-      ThumbprintList:
-        - 6938fd4d98bab03faadb97b34396831e3780aea1
-      Tags:
-        - Key: Name
-          Value: !Sub ${RoleName}-OIDC-Provider
-
-
-Outputs:
-
-  IdpGitHubOidc:
-    Description: "ARN of Github OIDC Provider"
-    Value: !GetAtt IdpGitHubOidc.Arn

package.json

@@ -1,7 +1,7 @@
 {
   "name": "configure-aws-credentials",
   "description": "A GitHub Action to configure AWS credentials",
-  "version": "6.2.2",
+  "version": "6.2.3",
   "scripts": {
     "build": "tsc",
     "lint": "biome check --error-on-warnings ./src ./test && markdownlint -i node_modules -i CHANGELOG.md '**/*.md'",
@@ -17,25 +17,26 @@
     "organization": true
   },
   "devDependencies": {
-    "@aws-sdk/credential-provider-env": "^3.972.49",
+    "@aws-sdk/credential-provider-env": "^3.972.70",
-    "@biomejs/biome": "2.5.2",
+    "@biomejs/biome": "2.5.10",
-    "@smithy/property-provider": "^4.4.6",
+    "@smithy/property-provider": "^4.5.2",
-    "@types/node": "^26.1.0",
+    "@types/node": "^26.2.0",
     "@vitest/coverage-v8": "4.1.10",
     "aws-sdk-client-mock": "^4.1.0",
-    "esbuild": "^0.28.1",
+    "esbuild": "^0.28.2",
     "generate-license-file": "^4.2.1",
     "json-schema": "^0.4.0",
-    "markdownlint-cli": "^0.49.0",
+    "markdownlint-cli": "^0.49.1",
-    "memfs": "^4.58.0",
+    "memfs": "^4.68.1",
     "standard-version": "^9.5.0",
-    "typescript": "^6.0.3",
+    "typescript": "^7.0.2",
     "vitest": "4.1.10"
   },
   "dependencies": {
     "@actions/core": "^3.0.1",
-    "@aws-sdk/client-sts": "^3.1080.0",
+    "@aws-sdk/client-sts": "^3.1116.0",
-    "@smithy/node-http-handler": "^4.9.1",
+    "@aws-sdk/credential-provider-node": "^3.972.63",
+    "@smithy/node-http-handler": "^4.11.3",
     "proxy-agent": "^8.0.2"
   },
   "keywords": [

src/CredentialsClient.ts

@@ -1,9 +1,10 @@
 import { info } from '@actions/core';
 import { STSClient } from '@aws-sdk/client-sts';
+import { defaultProvider } from '@aws-sdk/credential-provider-node';
 import type { AwsCredentialIdentity } from '@aws-sdk/types';
 import { NodeHttpHandler } from '@smithy/node-http-handler';
 import { ProxyAgent } from 'proxy-agent';
-import { buildCustomUserAgent, errorMessage, getCallerIdentity } from './helpers';
+import { buildCustomUserAgent, errorMessage, getCallerIdentity, maskProxyCredentials } from './helpers';
 import { ProxyResolver } from './ProxyResolver';
 
 if (!process.env.AWS_EXECUTION_ENV) {
@@ -31,6 +32,7 @@ export class CredentialsClient {
     }
     if (props.proxyServer) {
       info('Configuring proxy handler for STS client');
+      maskProxyCredentials(props.proxyServer);
       const proxyOptions: { httpProxy: string; httpsProxy: string; noProxy?: string } = {
         httpProxy: props.proxyServer,
         httpsProxy: props.proxyServer,
@@ -105,9 +107,15 @@ export class CredentialsClient {
   }
 
   private async loadCredentials() {
-    const config = {} as { requestHandler?: NodeHttpHandler };
+    // Previously we constructed a new client, but that picks up the default provider chain including the endpoint.
-    if (this.requestHandler !== undefined) config.requestHandler = this.requestHandler;
+    // Explicitly calling the default provider chain allows us to pass in the endpoint and region as well as the
-    const client = new STSClient(config);
+    // proxy config.
-    return client.config.credentials();
+    return defaultProvider({
+      clientConfig: {
+        ...(this.region !== undefined && { region: this.region }),
+        ...(this.stsEndpoint !== undefined && { endpoint: this.stsEndpoint }),
+        ...(this.requestHandler !== undefined && { requestHandler: this.requestHandler }),
+      },
+    })();
   }
 }

src/assumeRole.ts

@@ -2,11 +2,7 @@ import assert from 'node:assert';
 import path from 'node:path';
 import * as core from '@actions/core';
 import type { AssumeRoleCommandInput, STSClient, Tag } from '@aws-sdk/client-sts';
-import {
+import { AssumeRoleCommand, AssumeRoleWithWebIdentityCommand } from '@aws-sdk/client-sts';
-  AssumeRoleCommand,
-  AssumeRoleWithWebIdentityCommand,
-  PackedPolicyTooLargeException,
-} from '@aws-sdk/client-sts';
 import type { CredentialsClient } from './CredentialsClient';
 import { errorMessage, isDefined, readFileUtf8, sanitizeGitHubVariables } from './helpers';
 
@@ -65,7 +61,7 @@ async function assumeRoleWithCredentials(params: AssumeRoleCommandInput, client:
     const creds = await client.send(new AssumeRoleCommand({ ...params }));
     return creds;
   } catch (error) {
-    if (error instanceof PackedPolicyTooLargeException) {
+    if ((error as { name?: string })?.name === 'PackedPolicyTooLargeException') {
       core.info('Session tag size is too large; dropping droppable tags and retrying.');
       const droppableKeys = new Set(DROPPABLE_TAG_SOURCES.map((s) => s.key));
       params.Tags = params.Tags?.filter((tag) => !droppableKeys.has(tag.Key ?? ''));

src/helpers.ts

@@ -5,7 +5,6 @@ import type { Credentials, STSClient } from '@aws-sdk/client-sts';
 import { GetCallerIdentityCommand } from '@aws-sdk/client-sts';
 import type { AwsCredentialIdentity } from '@aws-sdk/types';
 import type { UserAgent } from '@smithy/types';
-import type { CredentialsClient } from './CredentialsClient';
 
 const MAX_TAG_VALUE_LENGTH = 256;
 const SANITIZATION_CHARACTER = '_';
@@ -167,15 +166,13 @@ export function exportAccountId(identity: { Account: string; Arn: string }, mask
 // Validates that the account of the already-resolved caller identity is in the allow-list provided via the
 // `allowed-account-ids` input.
 export function validateAccountId(expectedAccountIds: string[] | undefined, account: string | undefined): void {
-  if (!expectedAccountIds || expectedAccountIds.length === 0 || expectedAccountIds[0] === '') {
+  const allowedAccountIds = expectedAccountIds?.filter((id) => id !== '') ?? [];
+  if (allowedAccountIds.length === 0) {
     return;
   }
-  if (!account || !expectedAccountIds.includes(account)) {
+  if (!account || !allowedAccountIds.includes(account)) {
-    throw new Error(
+    // Account IDs are deliberately omitted: this error reaches the job log before any mask exists.
-      `The account ID of the provided credentials (${
+    throw new Error('The account ID of the provided credentials does not match any of the allowed account IDs');
-        account ?? 'unknown'
-      }) does not match any of the expected account IDs: ${expectedAccountIds.join(', ')}`,
-    );
   }
 }
 
@@ -193,6 +190,29 @@ export function toCredentialIdentity(creds?: Partial<Credentials>): AwsCredentia
   };
 }
 
+// Registers any userinfo embedded in a proxy URL as secrets so it is masked in job logs.
+// First the literal proxy string, then any username/password components if parseable.
+// If the username/password is percent-encoded, the decoded form is also masked.
+export function maskProxyCredentials(proxyServer: string): void {
+  core.setSecret(proxyServer);
+  let url: URL;
+  try {
+    url = new URL(proxyServer);
+  } catch (_) {
+    return;
+  }
+  for (const part of [url.username, url.password]) {
+    if (!part) continue;
+    core.setSecret(part);
+    try {
+      const decoded = decodeURIComponent(part);
+      if (decoded !== part) core.setSecret(decoded);
+    } catch (_) {
+      // malformed percent-encoding; the raw form is already masked
+    }
+  }
+}
+
 // Tags have a more restrictive set of acceptable characters than GitHub environment variables can.
 // This replaces anything not conforming to the tag restrictions by inverting the regular expression.
 // See the AWS documentation for constraint specifics https://docs.aws.amazon.com/STS/latest/APIReference/API_Tag.html.
@@ -260,13 +280,13 @@ export async function retryAndBackoff<T>(
         `Retrying after ${Math.floor(delay)}ms.`,
     );
 
-    await sleep(delay);
-
     if (nextRetry >= maxRetries) {
       core.info(`Retry${opName}: reached max retries (${maxRetries}); giving up.`);
       throw err;
     }
 
+    await sleep(delay);
+
     return await retryAndBackoff(fn, isRetryable, maxRetries, nextRetry, base, label);
   }
 }
@@ -281,19 +301,6 @@ export function isDefined<T>(i: T | undefined | null): i is T {
 }
 /* c8 ignore stop */
 
-export async function areCredentialsValid(credentialsClient: CredentialsClient) {
-  const client = credentialsClient.stsClient;
-  try {
-    const identity = await client.send(new GetCallerIdentityCommand({}));
-    if (identity.Account) {
-      return true;
-    }
-    return false;
-  } catch (_) {
-    return false;
-  }
-}
-
 /**
  * Like core.getBooleanInput, but respects the required option.
  *

src/index.ts

@@ -3,12 +3,12 @@ import type { AssumeRoleCommandOutput } from '@aws-sdk/client-sts';
 import { assumeRole } from './assumeRole';
 import { CredentialsClient } from './CredentialsClient';
 import {
-  areCredentialsValid,
   errorMessage,
   exportAccountId,
   exportCredentials,
   exportRegion,
   getBooleanInput,
+  getCallerIdentity,
   retryAndBackoff,
   toCredentialIdentity,
   translateEnvVariables,
@@ -53,8 +53,8 @@ export async function run() {
     });
     const roleChaining = getBooleanInput('role-chaining', { required: false });
     const outputCredentials = getBooleanInput('output-credentials', { required: false });
-    // Default to always outputting environment credentials unless profile is specified. If profile is specified, default
+    // Default to always outputting environment credentials unless profile is specified. If profile is specified,
-    // to no environment credentials (but still output them if the user specifically requests it).
+    // default to no environment credentials (but still output them if the user specifically requests it).
     const outputEnvCredentials = getBooleanInput('output-env-credentials', { required: false, default: !awsProfile });
     const unsetCurrentCredentials = getBooleanInput('unset-current-credentials', { required: false });
     let disableRetry = getBooleanInput('disable-retry', { required: false });
@@ -165,8 +165,16 @@ export async function run() {
 
     //if the user wants to attempt to use existing credentials, check if we have some already
     if (useExistingCredentials) {
-      const validCredentials = await areCredentialsValid(credentialsClient);
+      const identity = await (async () => {
-      if (validCredentials) {
+        try {
+          return await getCallerIdentity(credentialsClient.stsClient);
+        } catch {
+          return null;
+        }
+      })();
+      if (identity) {
+        // The allowed-account-ids guardrail applies to reused credentials too.
+        validateAccountId(expectedAccountIds, identity.Account);
         core.notice('Pre-existing credentials are valid. No need to generate new ones.');
         if (timeoutId) clearTimeout(timeoutId);
         return;

src/profileManager.ts

@@ -53,8 +53,15 @@ export function parseIni(iniData: string): Record<string, Record<string, string>
 export function stringifyIni(data: Record<string, Record<string, string>>): string {
   const sections: string[] = [];
   for (const [sectionName, sectionData] of Object.entries(data)) {
+    if (/[\r\n]/.test(sectionName)) {
+      throw new Error('INI section names must not contain newline characters');
+    }
     const lines: string[] = [`[${sectionName}]`];
     for (const [key, value] of Object.entries(sectionData)) {
+      // A newline in a key or value would inject arbitrary INI lines (e.g. credential_process).
+      if (/[\r\n]/.test(key) || /[\r\n]/.test(value)) {
+        throw new Error('INI keys and values must not contain newline characters');
+      }
       lines.push(`${key} = ${value}`);
     }
     sections.push(lines.join('\n'));

test/CredentialsClient.test.ts

@@ -0,0 +1,30 @@
+import { describe, expect, it, vi } from 'vitest';
+
+vi.mock('@aws-sdk/credential-provider-node', () => ({
+  defaultProvider: vi.fn(() => async () => ({ accessKeyId: 'AKIA', secretAccessKey: 'secret' })),
+}));
+
+import { defaultProvider } from '@aws-sdk/credential-provider-node';
+import { CredentialsClient } from '../src/CredentialsClient';
+
+describe('CredentialsClient', {}, () => {
+  it('pins ambient credential resolution to the configured region and STS endpoint', {}, async () => {
+    const client = new CredentialsClient({
+      region: 'eu-west-1',
+      stsEndpoint: 'https://sts.example.com',
+      roleChaining: false,
+    });
+    // biome-ignore lint/suspicious/noExplicitAny: any required to call private method
+    await (client as any).loadCredentials();
+    expect(defaultProvider).toHaveBeenCalledWith({
+      clientConfig: expect.objectContaining({ region: 'eu-west-1', endpoint: 'https://sts.example.com' }),
+    });
+  });
+
+  it('omits unset client config values from ambient credential resolution', {}, async () => {
+    const client = new CredentialsClient({ region: 'eu-west-1', roleChaining: false });
+    // biome-ignore lint/suspicious/noExplicitAny: any required to call private method
+    await (client as any).loadCredentials();
+    expect(defaultProvider).toHaveBeenLastCalledWith({ clientConfig: { region: 'eu-west-1' } });
+  });
+});

test/helpers.test.ts

@@ -126,6 +126,45 @@ describe('Configure AWS Credentials helpers', {}, () => {
     expect(core.exportVariable).toHaveBeenCalledWith('AWS_SESSION_TOKEN', '');
   });
 
+  describe('maskProxyCredentials', {}, () => {
+    it('masks username and password embedded in a proxy URL', {}, () => {
+      helpers.maskProxyCredentials('http://user:secretpass@proxy.example.com:8080');
+      expect(core.setSecret).toHaveBeenCalledWith('user');
+      expect(core.setSecret).toHaveBeenCalledWith('secretpass');
+    });
+
+    it('masks both encoded and decoded forms of the credentials', {}, () => {
+      helpers.maskProxyCredentials('http://user:p%40ss@proxy.example.com:8080');
+      expect(core.setSecret).toHaveBeenCalledWith('p%40ss');
+      expect(core.setSecret).toHaveBeenCalledWith('p@ss');
+    });
+
+    it('masks the whole value even without embedded credentials or when unparseable', {}, () => {
+      helpers.maskProxyCredentials('http://proxy.example.com:8080');
+      expect(core.setSecret).toHaveBeenCalledWith('http://proxy.example.com:8080');
+      helpers.maskProxyCredentials('not a url');
+      expect(core.setSecret).toHaveBeenCalledWith('not a url');
+      // no username/password parts, so exactly one mask per call
+      expect(core.setSecret).toHaveBeenCalledTimes(2);
+    });
+  });
+
+  describe('validateAccountId', {}, () => {
+    it('enforces the allow-list even when the first element is empty', {}, () => {
+      expect(() => helpers.validateAccountId(['', '999999999999'], '111111111111')).toThrow(/does not match/);
+    });
+
+    it('passes an allowed account despite empty entries in the list', {}, () => {
+      expect(() => helpers.validateAccountId(['', '111111111111'], '111111111111')).not.toThrow();
+    });
+
+    it('skips validation only when no non-empty entries exist', {}, () => {
+      expect(() => helpers.validateAccountId(undefined, '111111111111')).not.toThrow();
+      expect(() => helpers.validateAccountId([], '111111111111')).not.toThrow();
+      expect(() => helpers.validateAccountId([''], '111111111111')).not.toThrow();
+    });
+  });
+
   describe('filesystem helpers', {}, () => {
     describe('isSymlink', {}, () => {
       it('returns true for a symlink', {}, () => {

test/index.test.ts

@@ -3,7 +3,6 @@ import {
   AssumeRoleCommand,
   AssumeRoleWithWebIdentityCommand,
   GetCallerIdentityCommand,
-  PackedPolicyTooLargeException,
   STSClient,
 } from '@aws-sdk/client-sts';
 import { mockClient } from 'aws-sdk-client-mock';
@@ -331,10 +330,11 @@ describe('Configure AWS Credentials', {}, () => {
     });
     it('drops droppable tags and retries on PackedPolicyTooLargeException', {}, async () => {
       vi.mocked(core.getInput).mockImplementation(mocks.getInput(mocks.IAM_ASSUMEROLE_INPUTS));
-      mockedSTSClient
+      // Reject with a plain error carrying only the `name`, NOT an instance of the SDK class. This
-        .on(AssumeRoleCommand)
+      // mirrors the bundled action, where the error can be deserialized by a second, non-identical
-        .rejectsOnce(new PackedPolicyTooLargeException({ message: 'too large', $metadata: {} }))
+      // copy of PackedPolicyTooLargeException so `instanceof` fails; the recovery must key off `name`.
-        .resolvesOnce(mocks.outputs.STS_CREDENTIALS);
+      const packedPolicyError = Object.assign(new Error('too large'), { name: 'PackedPolicyTooLargeException' });
+      mockedSTSClient.on(AssumeRoleCommand).rejectsOnce(packedPolicyError).resolvesOnce(mocks.outputs.STS_CREDENTIALS);
       await run();
       expect(core.info).toHaveBeenCalledWith('Session tag size is too large; dropping droppable tags and retrying.');
       const retryInput = mockedSTSClient.commandCalls(AssumeRoleCommand)[1].args[0].input;
@@ -841,7 +841,7 @@ describe('Configure AWS Credentials', {}, () => {
 
       await run();
       expect(core.setFailed).toHaveBeenCalledWith(
-        'The account ID of the provided credentials (111111111111) does not match any of the expected account IDs: 999999999999',
+        'The account ID of the provided credentials does not match any of the allowed account IDs',
       );
     });
 
@@ -861,7 +861,7 @@ describe('Configure AWS Credentials', {}, () => {
 
       await run();
       expect(core.setFailed).toHaveBeenCalledWith(
-        'The account ID of the provided credentials (111111111111) does not match any of the expected account IDs: 999999999999, 888888888888',
+        'The account ID of the provided credentials does not match any of the allowed account IDs',
       );
     });
 
@@ -917,7 +917,7 @@ describe('Configure AWS Credentials', {}, () => {
 
       await run();
       expect(core.setFailed).toHaveBeenCalledWith(
-        'The account ID of the provided credentials (111111111111) does not match any of the expected account IDs: 999999999999',
+        'The account ID of the provided credentials does not match any of the allowed account IDs',
       );
     });
 
@@ -936,7 +936,7 @@ describe('Configure AWS Credentials', {}, () => {
 
       await run();
       expect(core.setFailed).toHaveBeenCalledWith(
-        'The account ID of the provided credentials (111111111111) does not match any of the expected account IDs: 999999999999',
+        'The account ID of the provided credentials does not match any of the allowed account IDs',
       );
     });
 
@@ -956,7 +956,7 @@ describe('Configure AWS Credentials', {}, () => {
 
       await run();
       expect(core.setFailed).toHaveBeenCalledWith(
-        'The account ID of the provided credentials (111111111111) does not match any of the expected account IDs: 999999999999',
+        'The account ID of the provided credentials does not match any of the allowed account IDs',
       );
     });
 
@@ -1015,6 +1015,33 @@ describe('Configure AWS Credentials', {}, () => {
       await run();
       expect(core.setFailed).not.toHaveBeenCalled();
     });
+
+    it('fails on the use-existing-credentials path when the account is not allowed', async () => {
+      vi.mocked(core.getInput).mockImplementation(
+        mocks.getInput({
+          ...mocks.USE_EXISTING_CREDENTIALS_INPUTS,
+          'allowed-account-ids': '999999999999',
+        }),
+      );
+      mockedSTSClient.on(GetCallerIdentityCommand).resolves({ ...mocks.outputs.GET_CALLER_IDENTITY });
+
+      await run();
+      expect(core.setFailed).toHaveBeenCalledWith(expect.stringContaining('does not match'));
+    });
+
+    it('reuses existing credentials when their account is allowed', async () => {
+      vi.mocked(core.getInput).mockImplementation(
+        mocks.getInput({
+          ...mocks.USE_EXISTING_CREDENTIALS_INPUTS,
+          'allowed-account-ids': '111111111111',
+        }),
+      );
+      mockedSTSClient.on(GetCallerIdentityCommand).resolves({ ...mocks.outputs.GET_CALLER_IDENTITY });
+
+      await run();
+      expect(core.notice).toHaveBeenCalledWith('Pre-existing credentials are valid. No need to generate new ones.');
+      expect(core.setFailed).not.toHaveBeenCalled();
+    });
   });
 
   describe('Global Timeout Configuration', {}, () => {
@@ -1240,6 +1267,21 @@ describe('Configure AWS Credentials', {}, () => {
 
       expect(core.setFailed).not.toHaveBeenCalled();
     });
+
+    it('masks credentials embedded in the proxy URL', async () => {
+      vi.mocked(core.getInput).mockImplementation(
+        mocks.getInput({
+          ...mocks.GH_OIDC_INPUTS,
+          'http-proxy': 'http://user:secretpass@proxy.example.com:8080',
+        }),
+      );
+
+      await run();
+
+      expect(core.setSecret).toHaveBeenCalledWith('user');
+      expect(core.setSecret).toHaveBeenCalledWith('secretpass');
+      expect(core.setFailed).not.toHaveBeenCalled();
+    });
   });
 
   describe('AWS Profile Support', {}, () => {

test/profileManager.test.ts

@@ -114,6 +114,22 @@ describe('Profile Manager', {}, () => {
       const result = stringifyIni({ dev: {} });
       expect(result).toBe('[dev]\n');
     });
+
+    it('rejects values containing newlines', {}, () => {
+      expect(() =>
+        stringifyIni({ dev: { aws_session_token: 'token\n[injected]\ncredential_process = evil' } }),
+      ).toThrow('must not contain newline characters');
+    });
+
+    it('rejects keys containing newlines', {}, () => {
+      expect(() => stringifyIni({ dev: { 'key\ninjected': 'val' } })).toThrow('must not contain newline characters');
+    });
+
+    it('rejects section names containing newlines', {}, () => {
+      expect(() => stringifyIni({ 'dev\r\n[injected]': { key: 'val' } })).toThrow(
+        'must not contain newline characters',
+      );
+    });
   });
 
   describe('validateProfileName', {}, () => {
@@ -423,6 +439,24 @@ describe('Profile Manager', {}, () => {
       expect(configParsed['profile dev'].region).toBe('us-east-1');
     });
 
+    it('refuses to write credentials containing newlines instead of injecting profiles', {}, () => {
+      expect(() =>
+        writeProfileFiles(
+          'dev',
+          {
+            AccessKeyId: 'AKIAIOSFODNN7EXAMPLE',
+            SecretAccessKey: 'wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY',
+            SessionToken: 'token\n[injected]\ncredential_process = evil-command',
+          },
+          'us-east-1',
+          false,
+        ),
+      ).toThrow('must not contain newline characters');
+
+      const credsPath = getProfileFilePaths().credentials;
+      expect(fs.existsSync(credsPath)).toBe(false);
+    });
+
     it('uses correct section naming for default profile', {}, () => {
       writeProfileFiles(
         'default',