CVE-2026-55196 (GCVE-0-2026-55196)

Vulnerability from cvelistv5 – Published: 2026-06-17 17:58 – Updated: 2026-06-17 17:58 X_Open Source
VLAI
Title
Hermes WebUI < 0.51.409 - Unauthenticated Passkey Registration via Authentication Bypass
Summary
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.
Severity
9.1 (Critical)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
9.1 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
CWE
  • CWE-306 - Missing Authentication for Critical Function
Assigner
References
Impacted products
Vendor Product Version
hermes-webui hermes-webui Affected: 0 , < 0.51.409 (semver)
Unaffected: 0.51.409 (semver)
Create a notification for this product.
Date Public
2026-06-14 00:00
Credits
Chia Min Jun Lennon
Show details on NVD website
To clipboard 

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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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Detection rules are retrieved from Rulezet.