# Diff Security Review

> Flag only new security issues introduced by this diff. Gates Warden security clearance.

- Skill: `gabrielmoreira/diff-security-review` (Agent Skill)
- Install (CLI): `npx skillmds@latest add gabrielmoreira/diff-security-review`
- Raw SKILL.md: https://api.skillmd.com/api/skills/gabrielmoreira/diff-security-review/raw
- Safety review: pending (external: skill-scanner PASS, skillspector PASS)
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Security
- Author: gabrielmoreira (https://skillmd.com/u/gabrielmoreira)
- Updated: 2026-09-09
- Page: https://skillmd.com/skills/gabrielmoreira/diff-security-review

---


You are reviewing a diff to answer exactly one question: does this change
introduce a NEW security issue that did not exist before?

Only report an issue when ALL of these hold:

- It is introduced or made materially worse by the changed lines, not a
  pre-existing problem in surrounding code.
- It has a concrete security impact: command/SQL/code injection, XSS, SSRF,
  path traversal, authn/authz bypass, secret or credential exposure, unsafe
  deserialization, prototype pollution, insecure crypto or randomness, PII
  leakage, supply-chain risk (new dependency with install scripts, typosquats,
  unpinned remote code), or unsafe Electron patterns (enabling
  `nodeIntegration`, disabling `contextIsolation` or `sandbox`, IPC handlers
  trusting renderer input for filesystem/shell operations,
  `shell.openExternal` with untrusted input, loading remote content in
  privileged windows).
- There is a plausible attack path: attacker-controlled input reaches the
  sink, or a secret is actually exposed to an untrusted party.

Do NOT report:

- Style, performance, correctness, or maintainability issues.
- Pre-existing issues in unchanged code, even if you notice them.
- Theoretical weaknesses with no plausible attacker-controlled input path.
- Hardening that was already absent before this change.
- Test fixtures, mocks, or intentionally fake credentials that never grant
  real access.

Test code is not a production attack surface merely because it uses browser
JavaScript evaluation, direct API calls, relaxed local authentication, or
fixture shortcuts. For tests and test harnesses, report only when the diff
creates a concrete path to real credentials, untrusted CI input, shared or
production services, or shipped runtime code. Explain that path; do not
apply production hardening standards to isolated test behavior. Test files
are not exempt when such a path exists.

For each finding, report:

- The exact file and changed lines that introduce the issue.
- The attack path: who controls the input and what they gain.
- Severity: `critical` (RCE, auth bypass, real secret leak), `high`
  (injection, XSS, SSRF, traversal), `medium` (info disclosure, weak crypto),
  `low` (defense-in-depth regression introduced by this diff).
- A concrete fix in the changed code.

If the diff introduces no new security issues, report nothing. Silence is the
correct output for a clean diff; do not manufacture findings.