38b298d5b2
Fixes anthropics/claude-plugins-official#2082 — diff feeders use git's
default quotePath setting, which C-quotes any path with a non-ASCII
byte. The downstream parsers in gitutil.parse_diff_into_files /
gitutil.extract_file_paths_from_diff match the diff header with
`re.match(r'^a/(.+?) b/(.+)$', ...)`, which only sees the raw
`a/path b/path` form. The C-quoted `"a/\303\201vila/..."` form
slips past the regex, the `continue` fires, and the file is silently
dropped from review.
Effect: a vulnerable file like `Ávila/payment.py` with
`os.system('curl ' + user_input)` never reaches the LLM reviewer.
False negative in exactly the direction the plugin exists to catch.
Sibling of #2056 / #2075: those fixed the UTF-8 decode of the
subprocess output (text=True crashed the reader thread on Windows
cp1252). This one fixes the diff-feeder commands themselves — the
name-only helpers (_git_name_only, _git_status_porcelain) already
pass core.quotePath=false for this exact reason; the diff-text
feeders were the holdouts.
Fix: add `-c core.quotePath=false` to 4 git invocations:
- gitutil._git_diff_range (push-sweep feed)
- gitutil.get_git_diff (Stop-hook feed)
- security_reminder_hook commit-review `git diff` (amend delta)
- security_reminder_hook commit-review `git show` (post-amend)
With the flag, git emits raw UTF-8 in the diff header
(`a/Ávila/payment.py`), the regex matches, and both files (the
non-ASCII vulnerable one + any ASCII control file) flow through to
review correctly.
Verified locally on macOS Python 3.13:
- py_compile clean on both files.
- Existing 45 smoke + extensibility tests still pass.
- 8 new tests in test_diff_parser_non_ascii.py (added to internal
test suite at sg-staging/tests/, not in this PR):
* 2 static-shape: gitutil._git_diff_range and get_git_diff both
contain `core.quotePath=false` in their source.
* 2 commit-review static: every subprocess.run in
handle_commit_review_posttooluse that mentions `"diff"` or
`"show"` also passes the flag. Catches the regression
class where a new diff/show call site is added without
plumbing the flag through.
* 4 end-to-end with a real git repo containing a
`Ávila/payment.py` baseline-and-edit:
- WITHOUT flag: header is C-quoted, both parsers drop the
non-ASCII file (demonstrates the bug).
- WITH flag: header is raw UTF-8, both parsers see the file.
- parse_diff_into_files (the other parse path) also keeps
the file with the flag.
- get_git_diff end-to-end produces unquoted output whose
file list includes the non-ASCII path.
- 53/53 pass total (45 existing + 8 new) in 3.41s.
NOT verified end-to-end with a real CC commit-review fire on a
non-ASCII path. The static-shape tests catch the regression and the
end-to-end git-repo tests pin parser behavior, but the actual
LLM-review-with-vuln-found path requires runtime verification against
an Anthropic-API-credentialed CC session.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
security-guidance
Security review for Claude-generated code. Three layers:
- Pattern warnings — instant regex-based reminders on
Edit/Writefor ~25 known-dangerous patterns (yaml.load,torch.load(weights_only=False),pickle.loadon untrusted data, rawinnerHTML, hardcoded secrets, etc.). - LLM diff review — when Claude finishes a turn, the plugin sends the diff to a fast LLM call (Opus 4.7 by default) and feeds high-severity findings back to Claude so it can fix them before you see the response.
- Agentic commit review — on
git commit, an SDK-driven reviewer reads related files (Read/Grep/Glob) to trace data flow across the codebase, catching multi-file vulnerabilities pattern matching misses (IDOR, auth bypass, cross-file SSRF).
Findings cover common web-vulnerability classes — injection, XSS, SSRF, hardcoded secrets, IDOR, auth bypass, unsafe deserialization, and path traversal among others.
Install
/plugin install security-guidance@claude-plugins-official
Marketplace ships enabled by default in Claude Code — no setup beyond having the CLI itself.
Prerequisites
- Claude Code CLI ≥ v2.1.144
- Python 3.8+ on
PATH(python3,python, orpy -3— the plugin picks the first that works) - A working API path (subscription, API key, or 3P provider config)
Configuration
All configuration is via environment variables. None are required for default behavior.
Selecting a model
# 1P / gateway: a canonical model id
SECURITY_REVIEW_MODEL=claude-opus-4-7 # default
# Bedrock: use the inference-profile id
SECURITY_REVIEW_MODEL=us.anthropic.claude-opus-4-7
# Vertex: use the Vertex date-tag form
SECURITY_REVIEW_MODEL=claude-opus-4-7@20260218
SECURITY_REVIEW_MODEL controls the LLM diff review. SG_AGENTIC_MODEL (same syntax) controls the agentic commit reviewer; defaults to the same model.
Enabling/disabling layers
| Variable | Default | What it does |
|---|---|---|
SECURITY_GUIDANCE_DISABLE=1 |
unset | Kill switch — disables the entire plugin |
ENABLE_PATTERN_RULES=0 |
on | Disable layer 1 (regex pattern warnings) |
ENABLE_CODE_SECURITY_REVIEW=0 |
on | Disable all LLM reviews (Stop hook + commit/push) |
ENABLE_STOP_REVIEW=0 |
on | Disable only the Stop-hook diff review, keeping commit/push reviews. Useful for multi-agent / shared-worktree setups where another agent can move HEAD between a worker's turns |
ENABLE_COMMIT_REVIEW=0 |
on | Disable layer 3 (agentic commit review) |
Higher-recall mode
SG_DUAL_OR=on # default off
Runs two parallel review calls and unions the findings. Catches a few percentage points more vulnerabilities in our testing, at roughly 2× the API cost per review. Most users don't need it.
Org-specific policies
Drop a claude-security-guidance.md in any of:
~/.claude/claude-security-guidance.md— user-wide rules<project>/.claude/claude-security-guidance.md— project rules, intended to be committed<project>/.claude/claude-security-guidance.local.md— local overrides, intended to be.gitignore'd
All three are loaded and concatenated into the LLM diff review's prompt in the order user → project → project-local. If the combined size exceeds the 8 KB prompt budget, the tail is truncated, so user-wide rules are kept and project-local rules are dropped first. The agentic commit reviewer (layer 3) does not currently read this file. Example:
# Acme security rules
- All SELECTs against the `customers` or `orders` tables MUST go through `db.replica`,
never `db.primary`. Primary is for writes only.
- Background jobs must not use the user-context auth token; they get
service-account creds from `jobs.get_service_account()`.
- Calls to `requests.get(url)` with a user-controlled `url` need
the SSRF-allowlist wrapper at `acme.net.safe_request`.
Built-in rules cover common web-vulnerability classes without it — claude-security-guidance.md is for things specific to your codebase that the model can't infer.
Privacy and data handling
The plugin sends data to a model endpoint to perform its reviews. Specifically, each Stop-hook diff review transmits the changed file paths, the diff hunks, and the relevant file contents in the diff; each agentic commit review additionally transmits any files the reviewer pulls in via Read/Grep/Glob while tracing data flow. Your claude-security-guidance.md contents (user, project, and local) are appended to the prompt on every review, so don't put secrets in it.
Where that data goes depends on your Claude Code configuration:
- Default (Anthropic API / subscription): sent to
api.anthropic.comand handled under Anthropic's Commercial Terms and Privacy Policy. - LLM gateway (
ANTHROPIC_BASE_URLset): sent to your gateway URL instead. The gateway operator's terms apply. - 3rd-party providers (Bedrock / Vertex / Foundry / Mantle): sent to your configured provider endpoint. The provider's data-handling terms apply (e.g., AWS / GCP / Azure).
The plugin writes its own debug log to ~/.claude/security/log.txt (override with SECURITY_GUIDANCE_DEBUG_LOG). The log contains diffstate metadata and finding categories — no full file contents or model prompts — and rotates at 1 MB. Nothing is uploaded.
Limitations
This is a best-effort assistive tool, not a guarantee. Treat findings as suggestions, not as a substitute for human code review, SAST/DAST, dependency scanning, or pen-testing. The reviewer can miss vulnerabilities, produce false positives, and may behave differently across codebases, languages, and model versions. No warranty is provided — use is subject to Anthropic's Commercial Terms.
Troubleshooting
Plugin doesn't seem to fire — check that ~/.claude/claude-security-guidance.md (or hook activity) shows in debug logs. Run Claude Code with --debug-file /tmp/claude/debug.txt and grep for security_reminder_hook. The plugin also writes its own log to ~/.claude/security/log.txt.
Review never finds anything — verify your API path works. On 3P providers, check SECURITY_REVIEW_MODEL is set to a provider-specific id (not a bare claude-opus-4-7). On LLM gateways, check the gateway's logs for POST /v1/messages traffic from the plugin.
Too many false positives — drop SECURITY_REVIEW_MODEL to a cheaper model (claude-sonnet-4-6) and re-evaluate; if precision is the priority, stay on Opus 4.7.
Want to silence a specific finding — add a comment to the line explaining why it's safe; the LLM reviewer treats inline justifications as exclusions. For systemic exclusions, document them in your claude-security-guidance.md.
Reporting issues
Open an issue on the security-guidance plugin repo with:
- The Claude Code CLI version (
claude --version) - Provider setup (1P / Bedrock / Vertex / LLM gateway / etc.)
- A minimal repro diff
- The relevant section of
~/.claude/security/log.txt