Security audit 2026-10-14: CI hardening and Dependabot security-only

.github/dependabot.yml

@@ -1,50 +1,57 @@
-# To get started with Dependabot version updates, you'll need to specify which
-# package ecosystems to update and where the package manifests are located.
-# https://docs.github.com/en/code-security/dependabot/dependabot-version-updates/configuration-options-for-the-dependabot.yml-file#versioning-strategy
+# Dependabot: security updates only (no version-update PRs).
+# Grouped security PRs open weekly on Tuesday morning (Europe/Bucharest).
+# Auto-merge: .github/workflows/dependabot-auto-merge.yml (on PR + Tuesday cron).
+# https://docs.github.com/en/code-security/dependabot/dependabot-security-updates
 
 version: 2
 updates:
-  # Keep the Java dependencies up to date
-  - package-ecosystem: "maven" # See documentation for possible values
-    directory: "/" # Location of package manifests
+  - package-ecosystem: "maven"
+    directory: "/"
     schedule:
-      interval: "weekly"
-      day: "monday"
-    target-branch: "master"
+      interval: weekly
+      day: tuesday
+      time: "06:00"
+      timezone: Europe/Bucharest
+    open-pull-requests-limit: 0
     labels:
+      - "dependabot-security"
       - "java dependencies"
     groups:
-      java:
-        applies-to: version-updates
+      maven-security:
+        applies-to: security-updates
         patterns:
-          - "*"       # A wildcard that matches all dependencies in the package
-
-  # Keep the Java dependencies up to date
-  - package-ecosystem: "maven" # See documentation for possible values
-    directory: "/zero-bounce-sdk/" # Location of package manifests
+          - "*"
+
+  - package-ecosystem: "maven"
+    directory: "/zero-bounce-sdk/"
     schedule:
-      interval: "weekly"
-      day: "monday"
-    target-branch: "master"
+      interval: weekly
+      day: tuesday
+      time: "06:00"
+      timezone: Europe/Bucharest
+    open-pull-requests-limit: 0
     labels:
+      - "dependabot-security"
       - "java dependencies"
     groups:
-      java:
-        applies-to: version-updates
+      maven-sdk-security:
+        applies-to: security-updates
         patterns:
-          - "*"       # A wildcard that matches all dependencies in the package
+          - "*"
 
-  # Keep the Github Actions dependencies up to date
-  - package-ecosystem: "github-actions" # See documentation for possible values
-    directory: "/" # Location of package manifests
+  - package-ecosystem: "github-actions"
+    directory: "/"
     schedule:
-      interval: "weekly"
-      day: "monday"
-    target-branch: "master"
+      interval: weekly
+      day: tuesday
+      time: "06:00"
+      timezone: Europe/Bucharest
+    open-pull-requests-limit: 0
     labels:
+      - "dependabot-security"
       - "github dependencies"
     groups:
-      github:
-        applies-to: version-updates
+      github-actions-security:
+        applies-to: security-updates
         patterns:
-          - "*"       # A wildcard that matches all dependencies in the package
+          - "*"

.github/workflows/auto_assign_ci.yaml

@@ -1,4 +1,5 @@
 name: Auto Assign
+# Audit 2026-10-14: pull_request_target — do not checkout the PR head here; configuration-path only.
 
 on:
   pull_request_target:
@@ -16,6 +17,6 @@ jobs:
     name: Auto assign (me only)
     runs-on: ubuntu-latest
     steps:
-      - uses: kentaro-m/auto-assign-action@v2.0.2
+      - uses: kentaro-m/auto-assign-action@0a2c53d3721e4c5cfcce6afd4014aecc337979f6 # v2.0.2
         with:
           configuration-path: ".github/auto_assign.yml"

.github/workflows/codeql.yml

@@ -63,7 +63,7 @@ jobs:
         # your codebase is analyzed, see https://docs.github.com/en/code-security/code-scanning/creating-an-advanced-setup-for-code-scanning/codeql-code-scanning-for-compiled-languages
     steps:
     - name: Checkout repository
-      uses: actions/checkout@v7
+      uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
 
     # Add any setup steps before running the `github/codeql-action/init` action.
     # This includes steps like installing compilers or runtimes (`actions/setup-node`
@@ -73,7 +73,7 @@ jobs:
 
     # Initializes the CodeQL tools for scanning.
     - name: Initialize CodeQL
-      uses: github/codeql-action/init@v4.37.9
+      uses: github/codeql-action/init@db488ddef3bf6cb639b32c2e9a7c0a7ea8271d28 # v4.37.9
       with:
         languages: ${{ matrix.language }}
         build-mode: ${{ matrix.build-mode }}
@@ -102,6 +102,6 @@ jobs:
         exit 1
 
     - name: Perform CodeQL Analysis
-      uses: github/codeql-action/analyze@v4.37.9
+      uses: github/codeql-action/analyze@db488ddef3bf6cb639b32c2e9a7c0a7ea8271d28 # v4.37.9
       with:
         category: "/language:${{matrix.language}}"

.github/workflows/dependabot-auto-merge.yml

@@ -0,0 +1,50 @@
+name: Dependabot security auto-merge
+
+on:
+  pull_request:
+    types: [opened, synchronize, reopened]
+  schedule:
+    - cron: "0 6 * * 2"
+      timezone: Europe/Bucharest
+
+permissions:
+  contents: write
+  pull-requests: write
+
+jobs:
+  approve-and-queue-merge:
+    runs-on: ubuntu-latest
+    if: >-
+      github.event_name == 'pull_request'
+      && github.event.pull_request.user.login == 'dependabot[bot]'
+    steps:
+      - name: Approve Dependabot pull request
+        run: gh pr review --approve "$PR_URL"
+        env:
+          PR_URL: ${{ github.event.pull_request.html_url }}
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Enable auto-merge when checks pass
+        run: gh pr merge --auto --merge "$PR_URL"
+        env:
+          PR_URL: ${{ github.event.pull_request.html_url }}
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+  weekly-merge-ready:
+    runs-on: ubuntu-latest
+    if: github.event_name == 'schedule'
+    steps:
+      - name: Approve and queue merge for open Dependabot PRs
+        run: |
+          set -euo pipefail
+          mapfile -t urls < <(gh pr list --author app/dependabot --state open --json url --jq '.[].url')
+          if [ "${#urls[@]}" -eq 0 ]; then
+            echo "No open Dependabot pull requests."
+            exit 0
+          fi
+          for url in "${urls[@]}"; do
+            gh pr review --approve "$url" || true
+            gh pr merge --auto --merge "$url" || true
+          done
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}

.github/workflows/publish.yml

@@ -13,26 +13,46 @@ permissions:
 
 jobs:
   validate-tag:
+    outputs:
+      tag_sha: ${{ steps.tag_sha.outputs.sha }}
     name: Validate tag
     runs-on: ubuntu-latest
     steps:
+      - name: Validate tag input
+        env:
+          TAG: ${{ github.event.inputs.tag }}
+        run: |
+          re='^v?[0-9]+\.[0-9]+\.[0-9]+([.+-][0-9A-Za-z.-]+)?$'
+          if [[ ! "$TAG" =~ $re ]]; then
+            echo "Error: the tag input must be a release tag such as v1.2.3."
+            exit 1
+          fi
+
       - name: Checkout
-        uses: actions/checkout@v7
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
         with:
           fetch-depth: 0
-
+          ref: refs/tags/${{ github.event.inputs.tag }}
+          persist-credentials: false
       - name: Verify tag exists
         run: |
           TAG="${{ github.event.inputs.tag }}"
           if [ -z "$TAG" ]; then
             echo "Error: Tag is required."
             exit 1
           fi
-          if ! git rev-parse "$TAG" >/dev/null 2>&1; then
+          if ! git rev-parse -q --verify "refs/tags/$TAG" >/dev/null; then
             echo "Error: Tag '$TAG' does not exist."
             exit 1
           fi
-          echo "Publishing tag: $TAG"
+
+      - name: Record tag commit SHA
+        id: tag_sha
+        env:
+          TAG: ${{ github.event.inputs.tag }}
+        run: |
+          SHA=$(git rev-parse "refs/tags/$TAG^{commit}")
+          echo "sha=$SHA" >> "$GITHUB_OUTPUT"
 
   publish:
     name: Test, release build and publish
@@ -41,12 +61,12 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout tag
-        uses: actions/checkout@v7
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
         with:
-          ref: ${{ github.event.inputs.tag }}
-
+          ref: ${{ needs.validate-tag.outputs.tag_sha }}
+          persist-credentials: false
       - name: Set up Maven Central Repository
-        uses: actions/setup-java@v6
+        uses: actions/setup-java@b843ebf9b913146b38da2eaa7aeddf76074ae1ad # v6
         with:
           java-version: 21
           distribution: 'temurin'
@@ -65,20 +85,21 @@ jobs:
 
   release:
     name: Create GitHub Release
-    needs: [publish]
+    needs: [validate-tag, publish]
     if: ${{ !cancelled() && !failure() }}
     runs-on: ubuntu-latest
     permissions:
       contents: write
     steps:
       - name: Checkout
-        uses: actions/checkout@v7
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
         with:
-          ref: ${{ github.event.inputs.tag }}
+          ref: ${{ needs.validate-tag.outputs.tag_sha }}
           fetch-depth: 0
 
+          persist-credentials: false
       - name: Create Release
-        uses: softprops/action-gh-release@v3.0.2
+        uses: softprops/action-gh-release@efb35369e0ad2afab669f228072c1b0d510eae64 # v3.0.3.0.2
         with:
           tag_name: ${{ github.event.inputs.tag }}
           name: ${{ github.event.inputs.tag }}

.github/workflows/sdk_ci.yml

@@ -15,10 +15,12 @@ jobs:
     name: Test & Lint
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v7
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          persist-credentials: false
 
       - name: Set up Maven Central Repository
-        uses: actions/setup-java@v6
+        uses: actions/setup-java@b843ebf9b913146b38da2eaa7aeddf76074ae1ad # v6
         with:
           java-version: 21
           distribution: 'temurin'

Dockerfile

@@ -10,4 +10,7 @@ WORKDIR /app/zero-bounce-sdk
 RUN mvn -q test
 
 # Default: run tests (re-run in case of docker run without build)
+
+USER 65532:65532
+
 CMD ["mvn", "-q", "test"]

zero-bounce-sdk/src/main/java/com/zerobounce/ZeroBounceSDK.java

@@ -1167,6 +1167,9 @@ private <T> void sendRequest(
             HttpURLConnection con = (HttpURLConnection) url.openConnection();
             con.setRequestProperty("Accept", "application/json");
 //            con.setRequestProperty("Content-Type", "application/json");
+            // Timeouts must be set before connect(); the POST branch connects explicitly below.
+            con.setConnectTimeout(timeoutInMillis);
+            con.setReadTimeout(timeoutInMillis);
 
             String httpMethod;
             if (body == null) {
@@ -1190,9 +1193,6 @@ private <T> void sendRequest(
 
             logDebug("ZeroBounceSDK::sendRequest executing " + httpMethod + " " + urlPath);
 
-            con.setConnectTimeout(timeoutInMillis);
-            con.setReadTimeout(timeoutInMillis);
-
             int status = con.getResponseCode();
             logDebug("ZeroBounceSDK::sendRequest status: " + status);
             Reader streamReader;