CVE-2026-55198
Deferred Deferred - Pending Action
Authorization Bypass in Hermes WebUI Session Export

Publication date: 2026-06-17

Last updated on: 2026-06-17

Assigner: VulnCheck

Description
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.
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Meta Information
Published
2026-06-17
Last Modified
2026-06-17
Generated
2026-06-18
AI Q&A
2026-06-18
EPSS Evaluated
N/A
NVD
CVE-2026-55198
EUVD
EUVD-2026-37779
Affected Vendors & Products
Showing 1 associated CPE
Vendor Product Version / Range
hermes hermes_webui to 0.51.443 (exc)
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Exploitability
CWE
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KEV
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CWE ID Description
CWE-639 The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data.
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Executive Summary

Hermes WebUI versions before 0.51.443 have an authorization bypass vulnerability in the session export endpoint. This vulnerability occurs because the _handle_session_export handler in the api/routes.py file does not verify whether the active user owns the profile whose session data is being requested. As a result, an authenticated user can access session data from other users' profiles by guessing or knowing their session identifiers.

Impact Analysis

This vulnerability allows an attacker who is authenticated to exfiltrate session transcripts belonging to other users. This means sensitive session information from other profiles can be accessed without proper authorization, potentially leading to privacy breaches or unauthorized data exposure.

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