CVE-2026-55197
Description
Hermes WebUI before 0.51.443 contains a broken access control vulnerability in the /api/session endpoint that allows authenticated users to disclose cross-profile session transcripts. Attackers can bypass profile boundary checks by directly querying session IDs belonging to other profiles via GET /api/session?session_id=<foreign_id>&messages=1 to retrieve unauthorized conversation transcripts and metadata.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or โ if you've already worked around this in production โ publish your fix to the community-verified tier.
โ Propose a mitigation on Community โ Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
References
- https://github.com/nesquena/hermes-webui/commit/2a3baa71b81ca92da8ece8616a09f15894beec71
- https://github.com/nesquena/hermes-webui/pull/3982
- https://github.com/nesquena/hermes-webui/pull/4269
- https://github.com/nesquena/hermes-webui/releases/tag/v0.51.443
- https://www.vulncheck.com/advisories/hermes-webui-broken-access-control-in-api-session-endpoint
CWEs
CWE-639
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.