PostHog / PostHog/warlock

New rule: detect suspicious encoded blobs in comments (beyond base64)

Open
#19 0 comments 0 reactions 0 assignees View on GitHub

Nobody has claimed this yet.

enhancement
Dominant language
TypeScript
Stars
0
Forks
1
PR merge metrics
No merged PRs in 30d

Description

Context

From Vincent's review on PR #12 — the current prompt_injection_base64_in_comment rule only catches base64. Other encoding schemes could also be used to smuggle payloads in comments.

What to catch

  • Long hex strings in comments (e.g., \x48\x65\x6c\x6c\x6f)
  • URL-encoded blobs (%48%65%6C%6C%6F)
  • Other obfuscation patterns (rot13, unicode escapes, etc.)

Considerations

  • High false-positive risk. Legitimate code comments often contain:
    • SHA hashes (40+ hex chars)
    • JWTs in test fixtures
    • UUIDs
    • Color codes, memory addresses
  • Needs careful threshold tuning per encoding type.
  • Better as companion rules (one per encoding type) rather than broadening the existing base64 rule.

Origin

PR #12 review comment by @gewenyu99

Contributor guide

Open the contributing guide

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Review PR #12 and the existing prompt_injection_base64_in_comment rule first. Determine which encoding-specific companion rules are in scope and set thresholds that distinguish encoded payloads from hashes, JWTs, UUIDs, color codes, and memory addresses. Done means the scope and false-positive safeguards are defined.

Written by the indexing model from the issue text.

Assessment

Tech stack
typescript
Domain
security
Issue type
Feature
Difficulty
5/5
Estimated time
Over a week
Activity status
Quiet
Clarity
Needs clarification
Newbie friendliness
35/100

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.