[plan] Fix high-severity template injection in cloclo.md

[github-actions]

Objective

Fix the HIGH severity template injection vulnerability in .github/workflows/cloclo.md by replacing envsubst with safe in-place string substitution.

Context

The cloclo.md workflow uses envsubst on potentially untrusted data from ${{ needs.activation.outputs.text }}, creating a code injection vulnerability. This is marked as HIGH severity in the static analysis.

Current Vulnerable Pattern

env:
  GH_AW_NEEDS_ACTIVATION_OUTPUTS_TEXT: ${{ needs.activation.outputs.text }}
run: |
  cat << 'PROMPT_EOF' | envsubst > "$GH_AW_PROMPT"
  [template content with $GH_AW_NEEDS_ACTIVATION_OUTPUTS_TEXT]
  PROMPT_EOF

Required Changes

1. Replace the envsubst pattern with sed-based substitution:

env:
  GH_AW_NEEDS_ACTIVATION_OUTPUTS_TEXT: ${{ needs.activation.outputs.text }}
run: |
  # Write template with placeholder directly to target file
  cat << 'PROMPT_EOF' > "$GH_AW_PROMPT"
  [template content with __GH_AW_NEEDS_ACTIVATION_OUTPUTS_TEXT__]
  PROMPT_EOF
  
  # Safely substitute using sed (escapes pipe character to avoid delimiter conflicts)
  sed -i "s|__GH_AW_NEEDS_ACTIVATION_OUTPUTS_TEXT__|${GH_AW_NEEDS_ACTIVATION_OUTPUTS_TEXT//|/\\|}|g" "$GH_AW_PROMPT"

2. Replace all $VAR references in the template with __VAR__ placeholders
3. Recompile the workflow: make recompile

Files to Modify

• .github/workflows/cloclo.md

Testing

Test the fix with malicious-looking input:

# Test content with shell metacharacters: $, `, \, $(), etc.
echo "Test: \$(malicious_command) and \`backdoor\` and \${VAR}"

Verify:

• Content is treated as literal text (not expanded)
• Workflow completes successfully
• Output contains the literal special characters
• No shell expansion occurs

Acceptance Criteria

• envsubst removed from cloclo.md
• Safe sed-based substitution implemented
• Template uses __VAR__ placeholder format
• No .template files created
• Workflow recompiled successfully
• Passes zizmor static analysis scan
• Manual test confirms no injection possible
  Related to [plan] Fix template injection vulnerabilities using in-place string substitution #5752

AI generated by Plan Command for discussion #5735