CVE-2026-55198
Hermes WebUI < 0.51.443 - Cross-Profile Session Data Exfiltration via Session Export Endpoint
CVSS Score
6.5
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-639 |
| Vendor | nesquena |
| Product | hermes-webui |
| Published | Jun 17, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None
Affected Versions
nesquena / hermes-webui
0 < 0.51.443
References
github.com: https://github.com/nesquena/hermes-webui/releases/tag/v0.51.443 github.com: https://github.com/nesquena/hermes-webui/pull/3991 github.com: https://github.com/nesquena/hermes-webui/pull/4269 github.com: https://github.com/nesquena/hermes-webui/commit/2a3baa71b81ca92da8ece8616a09f15894beec71 vulncheck.com: https://www.vulncheck.com/advisories/hermes-webui-cross-profile-session-data-exfiltration-via-session-export-endpoint
Credits
Chia Min Jun Lennon