CVE-2026-55197: Nesquena Hermes-Webui

Medium severity, CVSS 6.5. EPSS: 0.5% chance of exploitation in the next 30 days.

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.

Affected products

• Nesquena Hermes-Webui: before 0.51.443 (fixed in 0.51.443)

Published 2026-06-17. Last modified 2026-09-17.