What is CVE-2026-55196?

CVE-2026-55196 is a critical-severity vulnerability in Hermes-webui, classified under Missing Authentication for Critical Function. CVSS score: 9.1/10. Published 2026-06-17.

How severe is CVE-2026-55196?

Critical severity. CVSS v3 base score is 9.1 out of 10.

Auth bypass in Hermes-webui

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 exis…

Vulnerability class: Broken Authentication

CVSS v3 metric

CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N.

Affected products

Hermes-webui — versions 0, 0.51.409

Weakness classification (CWE)

CWE-306 — Missing Authentication for Critical Function

References

disclosure@vulncheck.com (release-notes)
disclosure@vulncheck.com (technical-description)
disclosure@vulncheck.com (issue-tracking)
disclosure@vulncheck.com (patch)
disclosure@vulncheck.com (third-party-advisory)

Frequently asked questions

What is CVE-2026-55196?: CVE-2026-55196 is a critical-severity vulnerability in Hermes-webui, classified under Missing Authentication for Critical Function. CVSS score: 9.1/10. Published 2026-06-17.
How severe is CVE-2026-55196?: Critical severity. CVSS v3 base score is 9.1 out of 10.