CVE-2026-55197

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.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
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

Configurations

No configuration.

History

17 Jun 2026, 20:21

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-17 19:18

Updated : 2026-06-17 20:21

NVD link : CVE-2026-55197

Mitre link : CVE-2026-55197

CVE.ORG link : CVE-2026-55197

JSON object : View

Products Affected

No product.

CWE

CWE-639

Authorization Bypass Through User-Controlled Key

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