CVE-2026-55196

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.

References

• 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