ClaudeKit Blender MCP

# Exhaustive Bug Investigation & Implementation Plan ## ClaudeKit Blender MCP - Complete Bug Fix Documentation **Investigation Date:** 2025-11-30 **Total Bugs Found:** 33 **Status:** Implementation Plan Ready --- ## Overview This directory contains comprehensive research findings and implementation plans for fixing 33 bugs discovered in the ClaudeKit Blender MCP codebase. The investigation covered security vulnerabilities, runtime errors, memory leaks, race conditions, type safety issues, and validation gaps. --- ## Directory Structure ``` 251130-2140-exhaustive-bug-investigation/ ├── README.md (this file) ├── IMPLEMENTATION-PLAN-SUMMARY.md - Quick reference guide ├── INDEX.md - Original investigation index ├── plan.md - Master implementation plan │ ├── Phase Implementation Plans: ├── phase-01-critical-security.md (2 bugs, 1 day) ├── phase-02-critical-stability.md (2 bugs, 1 day) ├── phase-03-high-priority.md (9 bugs, 2 days) ├── phase-04-medium-priority.md (12 bugs, 2 days) └── phase-05-low-cleanup.md (8 bugs, 1 day) │ ├── Research Reports: ├── research/ │ ├── researcher-01-runtime-types-memory.md (18 bugs) │ └── researcher-02-security-validation.md (15 bugs) │ └── Investigation Summaries: ├── BUGS-EXECUTIVE-SUMMARY.txt ├── INVESTIGATION-SUMMARY.txt └── scout/ (investigation artifacts) ``` --- ## Quick Start ### For Management 1. **Start here:** [IMPLEMENTATION-PLAN-SUMMARY.md](./IMPLEMENTATION-PLAN-SUMMARY.md) - High-level overview - Timeline and resource requirements - Risk assessment - Approval checklist ### For Engineers 1. **Read:** [plan.md](./plan.md) - Master plan overview 2. **Review:** Research reports in `./research/` 3. **Implement:** Phase-by-phase following phase documents 4. **Test:** Test plans included in each phase document ### For Security Team 1. **Priority:** [phase-01-critical-security.md](./phase-01-critical-security.md) - Path traversal vulnerability (CRITICAL) - Buffer overflow DoS (CRITICAL) 2. **Review:** [researcher-02-security-validation.md](./research/researcher-02-security-validation.md) ### For QA Team 1. **Test Plans:** Included in each phase document 2. **Security Tests:** Phase 1 penetration testing 3. **Load Tests:** Phase 2-3 race condition validation 4. **Memory Tests:** Phase 4 leak detection --- ## Bug Summary ### Critical Bugs (4) - Fix Day 1 | Bug ID | Description | File | Impact | |--------|-------------|------|--------| | RUNTIME_001 | Health check crash | index.ts | Server crash every 5min if check fails | | RACE_CONDITION_001 | Connection pool race | connection-pool.ts | Data corruption, concurrent socket access | | BUG-001 | Path traversal | validators.ts | Arbitrary file system access | | BUG-003 | Buffer overflow DoS | socket-client.ts | Memory exhaustion, service crash | ### High Severity (9) - Fix Day 2-4 - Socket error handler race - Event listener memory leak - Type safety issues - Cache key collision - Rate limit bypass - Regex ReDoS - Config validation bypass - Unhandled shutdown promises ### Medium Severity (12) - Fix Day 4-6 - Resource cleanup issues - Timer leaks - Validation gaps - Edge case handling - Race conditions in cleanup ### Low Severity (8) - Fix Day 6-7 - Code quality improvements - Minor validation enhancements - Logging consistency - Array growth optimization --- ## Implementation Timeline ``` 7-Day Implementation Plan ━━━━━━━━━━━━━━━━━━━━━━━━━━ Day 1: CRITICAL FIXES (Phase 1 + 2) ├─ Morning: Security vulnerabilities │ ├─ Path traversal fix │ └─ Buffer overflow protection └─ Afternoon: Stability crashes ├─ Health check error handling └─ Connection pool mutex Day 2-4: HIGH PRIORITY (Phase 3) ├─ Runtime error handling ├─ Memory leak fixes ├─ Type safety improvements └─ Security hardening Day 4-6: MEDIUM PRIORITY (Phase 4) ├─ Resource cleanup ├─ Validation enhancements └─ Edge case handling Day 6-7: LOW PRIORITY (Phase 5) ├─ Code quality ├─ Testing └─ Documentation ``` --- ## Files Modified **Total:** 13 files ### Core Infrastructure (6) - `src/index.ts` - Health check, shutdown - `src/utils/connection-pool.ts` - Race fixes, mutex - `src/utils/socket-client.ts` - Buffer limits, cleanup - `src/utils/health.ts` - Connection cleanup - `src/utils/rate-limiter.ts` - Overflow, cleanup - `src/utils/cache.ts` - Collision, TTL fixes ### Validation & Security (3) - `src/utils/validators.ts` - Path traversal, edge cases - `src/utils/config.ts` - Validation bypass - `src/tools/scripting.ts` - ReDoS, pattern evasion ### Supporting (4) - `src/utils/metrics.ts` - Array growth, timing - `src/utils/error-middleware.ts` - Enum indexing - `src/utils/logger.ts` - Console methods - `src/utils/file-utils.ts` - Stream errors --- ## Research Methodology ### Investigation Approach 1. **Scope Definition:** Runtime, security, memory, race conditions 2. **Static Analysis:** Manual code review of critical modules 3. **Pattern Detection:** Common vulnerability patterns 4. **Impact Assessment:** Severity classification 5. **Solution Design:** Fix strategies with risk analysis ### Researcher Coverage - **Researcher 01:** Runtime errors, type safety, memory leaks, race conditions (18 bugs) - **Researcher 02:** Security vulnerabilities, validation gaps, edge cases (15 bugs) ### Validation - Attack vector simulations - Edge case testing - Performance impact analysis - Backward compatibility review --- ## Key Findings ### Security Vulnerabilities (Critical) 1. **Path Traversal (BUG-001):** Blacklist approach can be bypassed with double encoding, URL encoding, null bytes 2. **Buffer Overflow (BUG-003):** No size limit on socket buffer accumulation - DoS via memory exhaustion 3. **Rate Limit Bypass (BUG-004):** Integer overflow under clock skew allows unlimited requests 4. **Cache DoS (BUG-002):** Regex injection can invalidate entire cache ### Runtime Failures (Critical) 1. **Health Check Crash (RUNTIME_001):** Unhandled promise rejection kills server every 5 minutes 2. **Connection Pool Race (RACE_CONDITION_001):** Concurrent acquire allows same socket to be used twice simultaneously ### Memory Leaks (High) 1. **Event Listeners (MEMORY_LEAK_001):** Accumulate unbounded if JSON parsing never completes 2. **Timer Leaks (MEMORY_LEAK_002, 003):** Intervals not cleared on failure or shutdown 3. **Connection Leaks (ASYNC_RACE_003, ASYNC_CLEANUP_001):** Sockets not properly closed on error ### Type Safety Issues (High) 1. **Unchecked Casts (TYPE_SAFETY_001):** JSON.parse result not validated before use 2. **Missing Validation (TYPE_SAFETY_002):** No null checks after type narrowing 3. **Unsafe Indexing (TYPE_SAFETY_003):** Enum values used without validation --- ## Testing Strategy ### Unit Testing - 95%+ coverage target for modified code - Each bug fix has dedicated test cases - Edge cases explicitly tested - Regression prevention ### Integration Testing - Full test suite after each phase - End-to-end scenarios - Cross-module interactions - Performance benchmarks ### Security Testing - Penetration testing for Phase 1 fixes - Attack vector simulations - Fuzzing for validation logic - Security scanning tools ### Load Testing - 1000 concurrent requests - 24-hour stability runs - Memory leak detection - Race condition stress testing --- ## Risk Management ### High-Risk Areas 1. **Connection Pool Refactoring** - Risk: Breaking existing functionality - Mitigation: Mutex with extensive testing - Rollback: Feature flag 2. **Path Validation Changes** - Risk: False positives on valid paths - Mitigation: Comprehensive test suite - Rollback: Relaxed validation mode 3. **Buffer Size Limits** - Risk: Reject legitimate large responses - Mitigation: 50MB limit based on analysis - Rollback: Configurable limit ### Deployment Strategy - Phase-by-phase deployment - Canary releases (5% → 100%) - 24-hour soak testing - Automated rollback < 5 minutes --- ## Success Criteria ### Technical Metrics - [ ] All 33 bugs verified fixed - [ ] 95%+ test coverage - [ ] 0 TypeScript errors - [ ] 0 ESLint warnings - [ ] 0 critical/high vulnerabilities - [ ] Response time maintained (< 5% increase) - [ ] No memory leaks (24-hour stable) ### Quality Metrics - [ ] Code review approved - [ ] Security review approved - [ ] Performance benchmarks passed - [ ] Documentation updated - [ ] No regressions detected ### Deployment Metrics - [ ] Staging validation successful - [ ] Canary deployment successful - [ ] Production monitoring green - [ ] Zero rollbacks required --- ## Documentation ### Technical Documentation - **Research Reports:** Detailed bug analysis in `./research/` - **Implementation Plans:** Phase-by-phase guides in root - **Test Plans:** Included in each phase document - **API Changes:** Documented in phase documents ### Process Documentation - **Timeline:** 7-day implementation schedule - **Resource Requirements:** Team allocation - **Risk Assessment:** Per-phase risk analysis - **Rollback Procedures:** Emergency recovery plans ### Post-Implementation - **CHANGELOG.md:** All 33 fixes documented - **SECURITY.md:** Security improvements - **TROUBLESHOOTING.md:** Common error scenarios - **Migration Guide:** Breaking changes (if any) --- ## Team Resources ### Implementation Team - **Lead Engineer:** Phase execution, code review - **Security Engineer:** Phase 1-3 review, penetration testing - **QA Engineer:** Test execution, validation - **DevOps Engineer:** Deployment, monitoring ### External Resources - **Security Team:** Phase 1 approval required - **Engineering Director:** Plan approval - **Product Team:** Validation rule review ### Tools Required - Jest (unit testing) - Artillery (load testing) - Valgrind/heapdump (memory profiling) - OWASP ZAP (security testing) - Snyk (dependency scanning) --- ## Approval & Sign-off ### Pre-Implementation Approvals - [ ] Engineering Lead: Plan review - [ ] Security Team: Phase 1-3 review - [ ] QA Team: Test plan review - [ ] DevOps Team: Deployment plan review ### Phase Completion Sign-off - [ ] Phase 1: Security Lead - [ ] Phase 2: Engineering Lead - [ ] Phase 3: Security + Engineering Leads - [ ] Phase 4: Engineering Lead - [ ] Phase 5: QA Lead ### Deployment Approval - [ ] All phases completed - [ ] All tests passing - [ ] Security scan clean - [ ] Performance acceptable - [ ] Documentation updated --- ## Contact & Support ### Questions About - **Implementation Plan:** Engineering Lead - **Security Fixes:** Security Team Lead - **Testing Strategy:** QA Engineer - **Deployment:** DevOps Team Lead ### Escalation Path 1. Phase lead 2. Engineering Lead 3. Engineering Director --- ## Revision History | Date | Version | Author | Changes | |------|---------|--------|---------| | 2025-11-30 | 1.0 | Implementation Planner | Initial plan created | --- ## Next Steps ### Immediate (Day 0) 1. Review and approve plan 2. Allocate team resources 3. Set up test environments 4. Schedule kickoff meeting ### Week 1 (Day 1-7) 1. Execute phases 1-5 2. Daily progress reviews 3. Continuous testing 4. Documentation updates ### Post-Implementation 1. Monitor production metrics 2. Collect lessons learned 3. Update processes 4. Plan preventive measures --- **Status:** Ready for Implementation **Approval Required:** Engineering Lead, Security Lead **Target Start Date:** TBD **Target Completion:** Start + 7 days --- ## Additional Resources - **Original Investigation:** See INDEX.md for investigation summary - **Bug Details:** See research reports for comprehensive analysis - **Code Examples:** Included in phase documents - **Test Cases:** Included in phase documents --- **For more information, start with [IMPLEMENTATION-PLAN-SUMMARY.md](./IMPLEMENTATION-PLAN-SUMMARY.md)**