{"id":"GHSA-pw5q-rjx4-7f7p","revision":"d692a9fd347b42e584d32e69246514c9","records":[{"revision":"d692a9fd347b42e584d32e69246514c9","observedAt":"2026-10-24T13:19:41.952+00:00","statement":{"source":"osv","id":"GHSA-pw5q-rjx4-7f7p","aliases":["CVE-2026-96627","GO-2026-6807"],"title":"Arcane: Delegated users:update permission allows admin account takeover via password reset (no privilege-hierarchy check)","description":"## Summary\nA user holding the delegated `users:update` permission can reset the global administrator's password and take over the admin account. `UpdateUser` sets the target user's `PasswordHash` from the request body for ANY target with no comparison of caller-vs-target privilege. Because role assignment and role CRUD are deliberately gated by `RequireGlobalAdmin`, `users:update` is intended to sit BELOW admin (profile management); this finding defeats that separation.\n\n## Root Cause\n`UpdateUser` (handler `backend/api/handlers/users.go:317-323`) loads the target by ID and sets `userModel.PasswordHash` from the request body for any user, then `userService.UpdateUser` (`user_service.go:174`) simply `tx.Save`s — with NO actor-vs-target privilege comparison. The only `IsGlobalAdmin` guard (`user_service.go:345`) is a last-admin check inside `DeleteUser`, not the update path. Role assignment / role CRUD are `RequireGlobalAdmin` (`backend/pkg/authz/permissions.go:27-33`), proving `users:update` is intended below admin.\n\n## Impact\nComplete administrator account takeover (C:H/I:H/A:H) by any holder of the delegated `users:update` permission.\n\n## Proof of Concept\n1. Admin delegates a custom \"User Manager\" role with `users:update`.\n2. `PUT /users/{adminId}` with `{\"password\":\"attacker123\"}`.\n3. `POST /auth/login {\"username\":\"arcane\",\"password\":\"attacker123\"}` → admin session.\n\n## Attack Chain\n1. Action: admin delegates custom role with `users:update`. Guard: role creation is `RequireGlobalAdmin`. Bypass: intended delegation (holder is meant to manage profiles, not seize admin).\n2. Action: `PUT /users/{adminId}` `{\"password\":\"attacker123\"}`. Guard: `RequirePermission(users:update)` (`users.go:154`). Bypass: holder has it; no hierarchy check (`users.go:317-323`, `user_service.go:174` unconditional Save).\n3. Action: `POST /auth/login` as admin → admin session.\n\n## Bypass Evidence\n- `users.go:317-323` sets `PasswordHash` for any target; `user_service.go:174-194` has no actor/target privilege comparison.\n- Only `IsGlobalAdmin` hits are `DeleteUser`'s last-admin guard and DTO flags (grep).\n- `users:update` is org-level, held by no built-in non-admin role (`permissions.go:24`).\n\n## Affected Versions\n`<= 2.5.0`.\n\nReported by **zx (Jace)** — GitHub: @manus-use","state":0,"publishedAt":"2026-10-16T21:15:03+00:00","modifiedAt":"2026-10-19T21:40:44.9325202+00:00","affected":[{"ecosystem":"Go","name":"github.com/getarcaneapp/arcane/backend/v2","ranges":[{"type":"SEMVER","events":[{"kind":"introduced","version":"0"},{"kind":"fixed","version":"2.6.0"}]}],"versions":[],"rawVersionEvidence":null}],"metrics":[{"system":"CVSS_V3","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":null,"severity":null},{"system":"Publisher rating","vector":null,"score":null,"severity":"HIGH"}],"references":["https://github.com/getarcaneapp/arcane/security/advisories/GHSA-pw5q-rjx4-7f7p","https://github.com/getarcaneapp/arcane/pull/3426","https://github.com/getarcaneapp/arcane/commit/21ea962f86d967dac8ae02a050f6e5f043d10fa1","https://github.com/getarcaneapp/arcane","https://github.com/getarcaneapp/arcane/releases/tag/backend/v2.6.0"],"sourceUrl":"https://github.com/advisories/GHSA-pw5q-rjx4-7f7p","license":"GitHub Advisory Database · CC-BY-4.0","key":"osv:GHSA-pw5q-rjx4-7f7p","identifiers":["GHSA-pw5q-rjx4-7f7p","CVE-2026-96627","GO-2026-6807"]},"retained":false,"historicalAffected":[]}],"coverage":[]}