diff --git a/.github/workflows/preview-smoke.yml b/.github/workflows/preview-smoke.yml
index 976882b..8226e9d 100644
--- a/.github/workflows/preview-smoke.yml
+++ b/.github/workflows/preview-smoke.yml
@@ -40,11 +40,20 @@ jobs:
     steps:
       - name: Decide
         id: check
+        env:
+          # Route PR body + fork flag through env vars instead of inline
+          # ${{ }} interpolation. Direct ${{ github.event.pull_request.body }}
+          # in a shell command pastes arbitrary user-controlled text (parens,
+          # backticks, pipes, heredocs) directly into the script — both a
+          # syntax-error risk AND a shell-injection vector. Quoting the env
+          # vars below makes both safe.
+          PR_BODY: ${{ github.event.pull_request.body }}
+          PR_IS_FORK: ${{ github.event.pull_request.head.repo.fork }}
         run: |
-          if [[ "${{ github.event.pull_request.head.repo.fork }}" == "true" ]]; then
+          if [[ "$PR_IS_FORK" == "true" ]]; then
             echo "should_run=false" >> $GITHUB_OUTPUT
             echo "::notice::Smoke skipped on fork PR (bypass secret unavailable to forks)"
-          elif echo "${{ github.event.pull_request.body }}" | grep -qE 'pipeline:.*skip.*\bsmoke\b'; then
+          elif echo "$PR_BODY" | grep -qE 'pipeline:.*skip.*\bsmoke\b'; then
             echo "should_run=false" >> $GITHUB_OUTPUT
             echo "::notice::Smoke skipped via pipeline directive"
           else
diff --git a/.github/workflows/visual-diff.yml b/.github/workflows/visual-diff.yml
index 8a12afa..75e3578 100644
--- a/.github/workflows/visual-diff.yml
+++ b/.github/workflows/visual-diff.yml
@@ -36,11 +36,16 @@ jobs:
       should_run: ${{ steps.check.outputs.should_run }}
     steps:
       - id: check
+        env:
+          # See preview-smoke.yml for the rationale: ${{ github.event.* }}
+          # inlined into shell is a syntax-error + injection vector.
+          PR_BODY: ${{ github.event.pull_request.body }}
+          PR_IS_FORK: ${{ github.event.pull_request.head.repo.fork }}
         run: |
-          if [[ "${{ github.event.pull_request.head.repo.fork }}" == "true" ]]; then
+          if [[ "$PR_IS_FORK" == "true" ]]; then
             echo "should_run=false" >> $GITHUB_OUTPUT
             echo "::notice::Visual diff skipped on fork PR (bypass secret unavailable to forks)"
-          elif echo "${{ github.event.pull_request.body }}" | grep -qE 'pipeline:.*skip.*\bvisual\b'; then
+          elif echo "$PR_BODY" | grep -qE 'pipeline:.*skip.*\bvisual\b'; then
             echo "should_run=false" >> $GITHUB_OUTPUT
             echo "::notice::Visual diff skipped via pipeline directive"
           else