{"document":{"category":"csaf_vex","csaf_version":"2.0","title":"CVE-2026-55196: Hermes WebUI < 0.51.409 - Unauthenticated Passkey Registration via Authentication Bypass","publisher":{"category":"vendor","name":"HarborGuard Database","namespace":"https://database.harborguard.co"},"tracking":{"id":"CVE-2026-55196","status":"final","version":"1","initial_release_date":"2026-06-17T17:58:56.543Z","current_release_date":"2026-06-17T17:58:56.543Z","revision_history":[{"date":"2026-06-17T17:58:56.543Z","number":"1","summary":"Initial machine-readable export from HarborGuard."}]},"distribution":{"tlp":{"label":"WHITE"},"text":"Public CVE data; freely redistributable."},"notes":[{"category":"description","text":"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.","title":"CVE description"}],"references":[{"category":"self","summary":"CVE-2026-55196 on HarborGuard Database","url":"https://database.harborguard.co/cve/CVE-2026-55196"},{"category":"external","summary":"CVE Record","url":"https://www.cve.org/CVERecord?id=CVE-2026-55196"},{"category":"external","summary":"Release Notes","url":"https://github.com/nesquena/hermes-webui/releases/tag/v0.51.442"},{"category":"external","summary":"Researcher Pull Request","url":"https://github.com/nesquena/hermes-webui/pull/4171"},{"category":"external","summary":"Maintainer Pull Request","url":"https://github.com/nesquena/hermes-webui/pull/4267"},{"category":"external","summary":"Patch Commit","url":"https://github.com/nesquena/hermes-webui/commit/4d90577e25d5537cb07290eca3fb8abff3bab316"},{"category":"external","summary":"vulncheck.com","url":"https://www.vulncheck.com/advisories/hermes-webui-unauthenticated-passkey-registration-via-authentication-bypass"}]},"product_tree":{"branches":[{"category":"vendor","name":"hermes-webui","branches":[{"category":"product_name","name":"hermes-webui","branches":[{"category":"product_version_range","name":"<0.51.409","product":{"name":"hermes-webui hermes-webui <0.51.409","product_id":"CSAFPID-1","product_identification_helper":{"cpe":"cpe:2.3:a:hermes-webui:hermes-webui:*:*:*:*:*:*:*:*"}}},{"category":"product_version","name":"0.51.409","product":{"name":"hermes-webui hermes-webui 0.51.409","product_id":"CSAFPID-2","product_identification_helper":{"cpe":"cpe:2.3:a:hermes-webui:hermes-webui:*:*:*:*:*:*:*:*"}}}]}]}]},"vulnerabilities":[{"cve":"CVE-2026-55196","title":"Hermes WebUI < 0.51.409 - Unauthenticated Passkey Registration via Authentication Bypass","notes":[{"category":"description","text":"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.","title":"CVE description"}],"product_status":{"known_affected":["CSAFPID-1"],"fixed":["CSAFPID-2"]},"scores":[{"cvss_v4":{"version":"4.0","vectorString":"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","baseScore":9.1,"baseSeverity":"CRITICAL"},"products":["CSAFPID-1"]}],"remediations":[{"category":"vendor_fix","details":"Update to a fixed version: 0.51.409.","product_ids":["CSAFPID-1"],"url":"https://github.com/nesquena/hermes-webui/commit/4d90577e25d5537cb07290eca3fb8abff3bab316"}]}]}