CVE-2026-55196

Hermes WebUI before 0.51.409 contains an authentication bypass vulnerability in passkey registration endpoints that allows unauthenticated remote attackers to register arbitrary passkeys. When HERMES_WEBUI_PASSKEY=1 is enabled with no existing credentials, POST /api/auth/passkey/register/options and POST /api/auth/passkey/register endpoints are accessible without authentication, allowing attackers to claim the first passkey and gain permanent administrative control.

CVSS v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/nesquena/hermes-webui/commit/4d90577e25d5537cb07290eca3fb8abff3bab316
https://github.com/nesquena/hermes-webui/pull/4171
https://github.com/nesquena/hermes-webui/pull/4267
https://github.com/nesquena/hermes-webui/releases/tag/v0.51.442
https://www.vulncheck.com/advisories/hermes-webui-unauthenticated-passkey-registration-via-authentication-bypass

Configurations

No configuration.

History

17 Jun 2026, 20:21

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-17 19:18

Updated : 2026-06-23 03:16

NVD link : CVE-2026-55196

Mitre link : CVE-2026-55196

CVE.ORG link : CVE-2026-55196

JSON object : View

Products Affected

No product.

CWE

CWE-306

Missing Authentication for Critical Function

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