{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-105211","assignerOrgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","state":"PUBLISHED","assignerShortName":"VulnCheck","dateReserved":"2026-10-04T13:02:21.188Z","datePublished":"2026-10-04T13:10:04.626Z","dateUpdated":"2026-10-05T14:06:56.950Z"},"containers":{"cna":{"providerMetadata":{"orgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","shortName":"VulnCheck","dateUpdated":"2026-10-04T13:10:04.626Z"},"datePublic":"2026-08-14T00:00:00.000Z","title":"ZITADEL before 4.17.1 Authentication Bypass via Login V2 OTP returnCode","descriptions":[{"lang":"en","value":"ZITADEL before 4.17.1 contains an authentication bypass vulnerability in Login V2 that allows unauthenticated attackers to take over accounts by obtaining OTP codes via the returnCode delivery type. Attackers knowing a login name of a victim with OTP-Email and OTP-SMS enrolled can read both codes from server-action responses to gain MFA-authenticated sessions, including administrator takeover."}],"problemTypes":[{"descriptions":[{"lang":"en","description":"Exposure of Sensitive Information to an Unauthorized Actor","cweId":"CWE-200","type":"CWE"}]}],"affected":[{"vendor":"zitadel","product":"zitadel","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","versionType":"semver","lessThan":"4.17.1"},{"version":"4.17.1","status":"unaffected","versionType":"semver"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:a:zitadel:zitadel:*:*:*:*:*:*:*:*","versionEndExcluding":"4.17.1"}]}]}],"metrics":[{"format":"CVSS","cvssV4_0":{"version":"4.0","vectorString":"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","attackVector":"NETWORK","attackComplexity":"HIGH","attackRequirements":"PRESENT","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"HIGH","vulnIntegrityImpact":"HIGH","vulnAvailabilityImpact":"HIGH","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":9.2,"baseSeverity":"CRITICAL"}},{"format":"CVSS","cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","attackVector":"NETWORK","attackComplexity":"HIGH","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH","baseScore":8.1,"baseSeverity":"HIGH"}}],"references":[{"url":"https://github.com/zitadel/zitadel/security/advisories/GHSA-3gwm-5wx8-4gm6","tags":["vendor-advisory"],"name":"GitHub Security Advisory (GHSA-3gwm-5wx8-4gm6)"},{"name":"VulnCheck Advisory: ZITADEL before 4.17.1 Authentication Bypass via Login V2 OTP returnCode","tags":["third-party-advisory"],"url":"https://www.vulncheck.com/advisories/zitadel-before-4.17.1-authentication-bypass-via-login-v2-otp-returncode"}],"credits":[{"lang":"en","value":"IAM-marco","type":"finder"},{"lang":"en","value":"livio-a","type":"finder"},{"lang":"en","value":"lucasdodgson","type":"reporter"}],"x_generator":{"engine":"vulncheck-endgame"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-10-05T14:06:47.384305Z","id":"CVE-2026-105211","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-10-05T14:06:56.950Z"}}]}}