vibeeval/differential-review
Security-focused differential code review with blast radius analysis, risk-adaptive depth (DEEP/FOCUSED/SURGICAL), git history correlation, and structured finding format. Adapted from Trail of Bits. Use when reviewing PRs, commits, or code changes for security implications.
npx skills add https://github.com/vibeeval/vibecosystem --skill differential-reviewSecurity-focused code review that adapts depth to codebase size and change risk. Goes beyond style -- finds vulnerabilities, logic errors, and blast radius.
Before reading any code:
# What changed?
git diff --stat <base>...<head>
# How much changed?
git diff --shortstat <base>...<head>
# Which files are security-sensitive?
git diff --name-only <base>...<head> | grep -iE '(auth|crypto|token|secret|permission|middleware|validator|sanitiz)'
Classify the change:
Check if the changed code has a history of bugs:
# How often has this file been changed? (churn = risk)
git log --oneline --follow <file> | wc -l
# Were there recent security fixes in this area?
git log --oneline --grep="fix\|vuln\|security\|CVE" -- <file>
# Who else has touched this code?
git log --format='%an' -- <file> | sort | uniq -c | sort -rn
High churn + security fix history = increase review depth.
For each changed file, analyze in this order:
## [SEVERITY] Finding Title
**Location**: file.ts:42-58
**Category**: [Input Validation | Auth | Crypto | Data Flow | State | Logic]
**Confidence**: [HIGH | MEDIUM | LOW]
**Description**:
What the vulnerability is, in one paragraph.
**Impact**:
What an attacker can achieve by exploiting this.
**Proof**:
The specific code path or data flow that demonstrates the issue.
**Recommendation**:
Concrete fix with code example if possible.
| Severity | Criteria | Examples |
|----------|----------|---------|
| CRITICAL | Remote exploitation, no auth required, data breach | SQL injection, auth bypass, RCE |
| HIGH | Requires some access, significant impact | Privilege escalation, IDOR, stored XSS |
| MEDIUM | Limited impact or complex exploitation | Reflected XSS, info disclosure, CSRF |
| LOW | Minimal impact, defense-in-depth | Missing headers, verbose errors, weak config |
| INFO | Best practice, no direct vulnerability | Code quality, missing rate limit, logging gap |
Common excuses that lead to missed findings. Do NOT accept these:
| Rationalization | Why It's Wrong | Required Action |
|----------------|---------------|-----------------|
| "It's behind auth" | Auth can be bypassed | Verify auth is enforced AND correct |
| "We trust this input" | Trust boundaries change | Validate at every boundary |
| "It's just internal" | Internal networks get compromised | Apply defense in depth |
| "Nobody would do that" | Attackers do unexpected things | Test the unexpected case |
| "We'll fix it later" | Later never comes in security | Flag it NOW with severity |
| "The framework handles it" | Frameworks have bypasses | Verify the framework actually applies |
| "It's the same as before" | Before might have been wrong too | Review the original if suspicious |
[ ] Blast radius assessed (files, trust boundaries, security controls)
[ ] Git history checked for churn and past security fixes
[ ] All new inputs validated
[ ] Auth/authz applied to new endpoints/paths
[ ] Error handling doesn't leak sensitive info
[ ] No hardcoded secrets or credentials
[ ] State mutations are atomic
[ ] Crypto usage follows current best practices
[ ] Logging doesn't include sensitive data
[ ] Removed code didn't contain security controls that are now missing
[ ] Dependencies added/updated are from trusted sources
[ ] Test coverage exists for security-critical paths
Inspired by Trail of Bits differential-review plugin.
Take vibeeval/differential-review from the repository into ~/.claude/skills for personal
use, or into .claude/skills inside a project.
The agent identifies a skill by the name field in its header. Two skills with the
same name cannot sit side by side — one of them will be ignored.