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Fix rate limiter bypass on websocket endpoint
71/100 High
71/100 High
Awaiting approval before merge.Risk score 71 exceeds threshold (50)
GitHub
Summary
Critical rate limiter fix for WebSocket connections — security improvement but high blast radius across middleware.
Model: claude-sonnet-4-20250514Duration: 11200msTokens: 3890
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Risk Scores
Overall71/100
Complexity40/100
Security82/100
Blast Radius65/100
Test Coverage55/100
Breaking Change50/100
File-Level Risk
| File | Risk | Category | Details |
|---|---|---|---|
src/middleware/rate-limiter.ts | 78 | security | Core rate limiting logic rewritten with token bucket algorithm |
src/ws/connection-manager.ts | 65 | blast Radius | Connection pool size change affects all WebSocket clients |
src/config/limits.ts | 42 | complexity | Rate limit config migrated from env vars to database |
src/middleware/ws-auth.ts | 35 | security | Auth check now runs before rate limit check (order change) |
tests/rate-limiter.test.ts | 15 | test Coverage | New tests but gaps in concurrent connection scenarios |
security
82/100Findings
- • Rate limiter bypass allows unlimited WebSocket connections from a single IP
- • Fix correctly applies token bucket algorithm per-connection
- • Missing rate limit headers in WebSocket upgrade response
Suggestions
- → Add X-RateLimit-* headers to WebSocket upgrade response
- → Consider implementing per-user rate limits in addition to per-IP
blast Radius
65/100Findings
- • Middleware change affects all WebSocket endpoints (5 routes)
- • Rate limit configuration moved from env to database — requires migration
- • Connection pool size reduced from 100 to 50 per-IP
Suggestions
- → Add feature flag to gradually roll out new rate limits
- → Document the connection pool size change in CHANGELOG
test Coverage
55/100Findings
- • Unit tests cover basic rate limiting logic
- • No load tests for concurrent WebSocket connections
- • Missing test for rate limit recovery after window expires
Suggestions
- → Add integration test simulating 100+ concurrent connections
- → Test rate limit header values in WebSocket upgrade response