diff --git a/.github/workflows/spam-detection-adk-java-issues.yml b/.github/workflows/spam-detection-adk-java-issues.yml
index de7841d3d..4fb1451fd 100644
--- a/.github/workflows/spam-detection-adk-java-issues.yml
+++ b/.github/workflows/spam-detection-adk-java-issues.yml
@@ -51,10 +51,10 @@ jobs:
 
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v6
+        uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6
 
       - name: Set up Java
-        uses: actions/setup-java@v5
+        uses: actions/setup-java@1bcf9fb12cf4aa7d266a90ae39939e61372fe520 # v5
         with:
           distribution: temurin
           java-version: '17'
@@ -76,8 +76,9 @@ jobs:
           DRY_RUN: '1'
           EVENT_NAME: ${{ github.event_name }}
           ISSUE_NUMBER: ${{ github.event.issue.number }}
-          ISSUE_TITLE: ${{ github.event.issue.title }}
-          ISSUE_BODY: ${{ github.event.issue.body }}
+          # ISSUE_TITLE and ISSUE_BODY intentionally omitted: passing raw GitHub event
+          # content directly as env vars is a prompt-injection vector. The agent
+          # must fetch issue content via the GitHub API using ISSUE_NUMBER instead.
           # Mapped to the manual-dispatch checkbox. On the daily schedule this is
           # empty, so only issues updated in the last 24h are audited.
           INITIAL_FULL_SCAN: ${{ github.event.inputs.full_scan }}
diff --git a/.github/workflows/triage-adk-java-issues.yml b/.github/workflows/triage-adk-java-issues.yml
index 972a9ef35..9f76dd1da 100644
--- a/.github/workflows/triage-adk-java-issues.yml
+++ b/.github/workflows/triage-adk-java-issues.yml
@@ -41,10 +41,10 @@ jobs:
 
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v6
+        uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6
 
       - name: Set up Java
-        uses: actions/setup-java@v5
+        uses: actions/setup-java@1bcf9fb12cf4aa7d266a90ae39939e61372fe520 # v5
         with:
           distribution: temurin
           java-version: '17'
@@ -66,8 +66,9 @@ jobs:
           DRY_RUN: '1'
           EVENT_NAME: ${{ github.event_name }}
           ISSUE_NUMBER: ${{ github.event.issue.number }}
-          ISSUE_TITLE: ${{ github.event.issue.title }}
-          ISSUE_BODY: ${{ github.event.issue.body }}
+          # ISSUE_TITLE and ISSUE_BODY intentionally omitted: passing raw GitHub event
+          # content directly as env vars is a prompt-injection vector. The agent
+          # must fetch issue content via the GitHub API using ISSUE_NUMBER instead.
           # Number of issues to process per scheduled batch run.
           ISSUE_COUNT_TO_PROCESS: '3'
           # Comma-separated GitHub handles to round-robin assign issues to.