CVE-2026-55198 (GCVE-0-2026-55198)
Vulnerability from cvelistv5 – Published: 2026-06-17 17:59 – Updated: 2026-09-17 18:57 X_Open Source
VLAI
EPSS
VEX
Title
Hermes WebUI < 0.51.443 - Cross-Profile Session Data Exfiltration via Session Export Endpoint
Summary
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.
Severity
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-17 19:30 UTC
CWE
- CWE-639 - Authorization Bypass Through User-Controlled Key
Assigner
References
5 references
| URL | Tags |
|---|---|
| https://github.com/nesquena/hermes-webui/releases… | release-notes |
| https://github.com/nesquena/hermes-webui/pull/3991 | issue-trackingpatch |
| https://github.com/nesquena/hermes-webui/pull/4269 | issue-trackingpatch |
| https://github.com/nesquena/hermes-webui/commit/2… | patch |
| https://www.vulncheck.com/advisories/hermes-webui… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| nesquena | hermes-webui |
Affected:
0 , < 0.51.443
(semver)
Unaffected: 0.51.443 (semver) cpe:2.3:a:get-hermes:hermes_web_ui:*:*:*:*:*:*:*:* |
Date Public
2026-06-11 00:00
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Sightings
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