CVE-2026-55197

EUVD-2026-37778
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.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
6.5 MEDIUM
NETWORK
LOW
LOW
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Awaiting analysis
This vulnerability is currently awaiting analysis.
Base Score
CVSS 3.x
EPSS Score
Percentile: Unknown
Common Weakness Enumeration
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
https://github.com/nesquena/hermes-webui/pull/3982