{"id":"CVE-2026-105210","state":"PUBLISHED","title":"ZITADEL before 4.17.1 Unauthenticated MFA Enrollment via Login V1 Init Handlers","description":"ZITADEL 3.x before 3.4.15 and 4.x before 4.17.1 contains a missing authentication flaw in the hosted Login V1 UI, whose second-factor enrollment and initialization handlers act on an identify-only session before any primary factor is verified. Attackers knowing only a victim's login name can enroll attacker-controlled TOTP, OTP-SMS, OTP-Email, or U2F factors, overwrite the verified phone number, and enumerate users through discrepant errors.","publishedAt":"2026-10-04T13:10:03.949Z","updatedAt":"2026-10-29T21:15:33.072Z","severity":{"score":8.8,"label":"High","version":"4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N","source":"VulnCheck"},"assigner":"VulnCheck","products":["zitadel zitadel"],"affected":[{"vendor":"zitadel","product":"zitadel","defaultStatus":"unaffected","versions":[{"version":"4.0.0","status":"affected","lessThan":"4.17.1","versionType":"semver"},{"version":"4.17.1","status":"unaffected","versionType":"semver"}]},{"vendor":"zitadel","product":"zitadel","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThan":"3.4.15","versionType":"semver"},{"version":"3.4.15","status":"unaffected","versionType":"semver"}]}],"references":["https://github.com/zitadel/zitadel/security/advisories/GHSA-72q5-mv5c-vxv4","https://www.vulncheck.com/advisories/zitadel-before-4.17.1-unauthenticated-mfa-enrollment-via-login-v1-init-handlers"],"weaknesses":["CWE-287"],"ingestedAt":"2026-10-29T23:08:31.977Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/105xxx/CVE-2026-105210.json","commit":"dc7676b3f67d6707e4927968546e7e0125ff7ec7","baselineCommit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-105210","state":"PUBLISHED","datePublished":"2026-10-04T13:10:03.949Z","dateUpdated":"2026-10-29T21:15:33.072Z","assignerShortName":"VulnCheck","assignerOrgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","dateReserved":"2026-10-04T13:02:21.188Z"},"containers":{"cna":{"title":"ZITADEL before 4.17.1 Unauthenticated MFA Enrollment via Login V1 Init Handlers","descriptions":[{"lang":"en","value":"ZITADEL 3.x before 3.4.15 and 4.x before 4.17.1 contains a missing authentication flaw in the hosted Login V1 UI, whose second-factor enrollment and initialization handlers act on an identify-only session before any primary factor is verified. Attackers knowing only a victim's login name can enroll attacker-controlled TOTP, OTP-SMS, OTP-Email, or U2F factors, overwrite the verified phone number, and enumerate users through discrepant errors."}],"affected":[{"vendor":"zitadel","product":"zitadel","defaultStatus":"unaffected","versions":[{"version":"4.0.0","status":"affected","lessThan":"4.17.1","versionType":"semver"},{"version":"4.17.1","status":"unaffected","versionType":"semver"}]},{"vendor":"zitadel","product":"zitadel","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThan":"3.4.15","versionType":"semver"},{"version":"3.4.15","status":"unaffected","versionType":"semver"}]}],"references":[{"url":"https://github.com/zitadel/zitadel/security/advisories/GHSA-72q5-mv5c-vxv4","tags":["vendor-advisory"],"name":"GitHub Security Advisory (GHSA-72q5-mv5c-vxv4)"},{"url":"https://www.vulncheck.com/advisories/zitadel-before-4.17.1-unauthenticated-mfa-enrollment-via-login-v1-init-handlers","name":"VulnCheck Advisory: ZITADEL before 4.17.1 Unauthenticated MFA Enrollment via Login V1 Init Handlers","tags":["third-party-advisory"]}],"metrics":[{"format":"CVSS","cvssV4_0":{"version":"4.0","vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N","attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"LOW","vulnIntegrityImpact":"HIGH","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":8.8,"baseSeverity":"HIGH"}},{"format":"CVSS","cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"LOW","integrityImpact":"HIGH","availabilityImpact":"NONE","baseScore":8.2,"baseSeverity":"HIGH"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-287","lang":"en","description":"Improper Authentication","type":"CWE"}]}],"providerMetadata":{"shortName":"VulnCheck","orgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","dateUpdated":"2026-10-29T21:15:33.072Z"},"datePublic":"2026-08-14T00:00:00.000Z","cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:a:zitadel:zitadel:*:*:*:*:*:*:*:*","versionEndExcluding":"4.17.1","versionStartIncluding":"4.0.0"}]}]},{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:a:zitadel:zitadel:*:*:*:*:*:*:*:*","versionEndExcluding":"3.4.15"}]}]}],"credits":[{"lang":"en","value":"grvijayan","type":"finder"},{"lang":"en","value":"livio-a","type":"finder"},{"lang":"en","value":"lucasdodgson","type":"reporter"},{"lang":"en","value":"AdamKorcz","type":"reporter"}],"x_generator":{"engine":"vulncheck-endgame"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-10-05T13:29:04.590483Z","id":"CVE-2026-105210","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-05T13:29:17.102Z"}}]}}}