CVE-2026-55198: 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 an authorization bypass vulnerability in the session export endpoint that allows authenticated users to access sessions from other profiles. The _handle_session_export handler in api/routes.py fails to verify active-profile ownership before serializing session data, enabling attackers to exfiltrate foreign session transcripts by guessing or knowing session identifiers.

Affected products

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

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