CVE-2026-55198

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.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/nesquena/hermes-webui/commit/2a3baa71b81ca92da8ece8616a09f15894beec71
https://github.com/nesquena/hermes-webui/pull/3991
https://github.com/nesquena/hermes-webui/pull/4269
https://github.com/nesquena/hermes-webui/releases/tag/v0.51.443
https://www.vulncheck.com/advisories/hermes-webui-cross-profile-session-data-exfiltration-via-session-export-endpoint
https://github.com/nesquena/hermes-webui/pull/3991

Configurations

No configuration.

History

17 Jun 2026, 20:21

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-17 19:18

Updated : 2026-06-17 20:21

NVD link : CVE-2026-55198

Mitre link : CVE-2026-55198

CVE.ORG link : CVE-2026-55198

JSON object : View

Products Affected

No product.

CWE

CWE-639

Authorization Bypass Through User-Controlled Key

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