docs(buglog): P0 defects fixed (bug-1936..bug-1955; 1936 and 1955 partial), bug-1956 cannot-reproduce

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

.wolf/bugs/bug-1950.md

@@ -1,8 +1,8 @@
 ---
 id: "bug-1950"
-status: "open"
+status: "fixed"
 status_updated: "2026-10-10"
-status_note: "newly logged"
+status_note: ""
 component: "apiserver"
 severity: "security"
 timestamp: "2026-10-10T08:15:11Z"
@@ -11,6 +11,7 @@ occurrences: 1
 files: ["src/frontend/apiserver/middleware/validatehandler.go"]
 tags: ["apiserver", "security", "jwt"]
 related: []
+fix_commits: ["42dd1e7a"]
 ---
 
 # bug-1950: apiserver JWT validation does not pin the signing algorithm
@@ -35,15 +36,16 @@ The middleware's parse callback returns the key without checking `token.Method`
 - Frequency: deterministic (by code reading; confirmed by the RED test of the fix)
 - Evidence: the code sites quoted in Description; no logs kept.
 ## Root cause
-TODO: required for fixed/partial
+`isValidToken()` (`middleware/validatehandler.go`) never checked `token.Method`; `GetUsernameFromToken` accepted any HMAC variant.
 
 ## Fix
-TODO: required for fixed/partial
+`controllers/auth.go`: `JWTSigningMethod` (HS256), `JWTKeyFunc`, `JWTValidMethods()`; both parse paths use them.
 
 ## Verification
-- Test: TODO: name + file; RED before the fix, GREEN after
-- Suites: TODO: suite results and build profile
-- Live: TODO: soak/deploy run, or n/a and why
+- Test: `TestIsValidToken_PinsSigningAlgorithm` (`middleware/validatehandler_test.go`): RED `isValidToken(HS384) = true, want false`; `TestGetUsernameFromToken_PinsSigningAlgorithm`: RED; GREEN after.
+- Suites: `xce-build.sh all asan xce.build --incremental` on the merged branch, 2026-10-10: all C suites Ok 155 / Fail 0, frontend Go unit tests ok, xceadmin tests ok; apiserver `CGO_ENABLED=0 go test ./...` (incl. middleware, router, cmd) ok
+- Live: n/a: unit/fixture-level verification only; no live deployment was run (follow-up)
 
 ## References
-- Related: none
+- Fix commit: `42dd1e7a` (on `scheduler-framework`; worker-branch original in the merge)
+- Review: `.kiro/reviews/project-gap-review-2026-10-10.md`