APR-Lite Phase 37: Security Hardening & Vulnerability Remediation

This document is the canonical technical record for APR-Lite Phase 37, a dedicated security hardening phase conducted via static code audit of the v8.3.0-p36.0 worker. The audit identified eleven vulnerabilities across four severity levels. Ten were closed in this phase; one was deferred. Phase 37 introduces no new governance capabilities — it hardens the substrate against actor spoofing, CORS misconfiguration, SSRF patterns, unauthenticated endpoint exposure, chain health measurement error, information leakage, constant-time comparison (deferred), unbounded resource growth, and chain walk completeness. Both the governance validation suite (23 tests) and the security regression suite (21 tests) pass at 100% after remediation. Phase 37 establishes the principle that static audit is a required complement to behavioral test suites: tests validate correct behavior; audits find structural problems that correct behavior can coexist with. Audit Methodology Phase 37 was conducted via static analysis of the Worker source file. No credentials were used during the audit phase. Vulnerabilities were identified by reading function bodies, tracing authentication coverage, inspecting input validation, reviewing CORS configuration, analyzing SSRF patterns, and checking operator precedence. A behavioral test suite cannot find structural vulnerabilities — both disciplines are required.