by Kastro
Paper/Archive/CVE-2026-55196

CVE-2026-55196

hermes-webui hermes-webui — Hermes WebUI < 0.51.409 - Unauthenticated Passkey Registration via Authentication Bypass

EPSS 0.6%CVSS 9.1
critical.is priorityof 100
37
CVSS 9.1 (CNA)9.1 / 10 × 3027.3Not in CISA KEV+300.0EPSS percentile 47.6.476 × 209.5No public exploit+100.0SSVC exploitation: none+100.0
Description · from the CVE record

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.

Affected

ProductAffectedFixed inSource
hermes-webui< 0.51.4090.51.409CNA

Scores by source

VulnCheck (CNA)9.1CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
VulnCheck (CNA)9.1CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
CISA ADPSSVCExploitation: none · Automatable: yes · Technical impact: total

References

refgithub.com/nesquena/hermes-webui/releases/tag/v0.51.442patchgithub.com/nesquena/hermes-webui/pull/4171patchgithub.com/nesquena/hermes-webui/pull/4267patchgithub.com/nesquena/hermes-webui/commit/4d90577e25d5537cb07290eca3fb8abff3bab316writeupvulncheck.com/advisories/hermes-webui-unauthenticated-passkey-registration-via-authentication-bypass