CVE-2026-55196 Details
Description
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.
An authentication bypass vulnerability has been identified in Hermes WebUI versions prior to 0.51.409. This vulnerability allows unauthenticated remote attackers to register arbitrary passkeys. When the passkey feature is enabled and no credentials are set up, the passkey registration endpoints can be accessed without authentication. This exploitation enables attackers to claim the first passkey, thereby gaining permanent administrative control.
Users can update to Hermes WebUI version 0.51.442 or later, where this vulnerability has been addressed.
Metrics
CVSS 4.0 Severity and Vector Strings:
VolerionCVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
Volerion
Assessed Jun 17, 2026CISA-ADP
Assessed Jun 23, 2026References to Advisories, Solutions, and Tools
By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.
| URL | Source(s) | Tag(s) |
|---|---|---|
| https://github.com/nesquena/hermes-webui/commit/4d90577e25d5537cb07290eca3fb8abff3bab316 | [email protected] | Source CodeVendor |
| https://github.com/nesquena/hermes-webui/pull/4171 | [email protected] | Issue TrackingVendor |
| https://github.com/nesquena/hermes-webui/pull/4267 | [email protected] | Issue TrackingVendor |
| https://github.com/nesquena/hermes-webui/releases/tag/v0.51.442 | [email protected] | Release NotesVendor |
| https://www.vulncheck.com/advisories/hermes-webui-unauthenticated-passkey-registration-via-authentication-bypass | [email protected] | AdvisoryRemedy |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-306 | Missing Authentication for Critical Function | [email protected] |
Affected Products
| Product | Versions |
|---|---|
| Hermes WebUI | < 0.51.409 (semver) |
CPE
Remediation
| |
Change History
3 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Sep 17, 2026 | CVE Modified | [email protected] |
| Jun 23, 2026 | CVE Modified | CISA-ADP |
| Jun 17, 2026 | New CVE Received | [email protected] |