{"id":"CVE-2026-105211","title":"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","summary":"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 vi…","severity":"high","cvss":8.1,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-200"],"vendor":"zitadel","product":"zitadel","affected":["zitadel < 4.17.1"],"published":"2026-10-04","updated":"2026-10-04","sourceUpdated":"2026-10-04T15:16:32.467","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-105211","references":[{"url":"https://github.com/zitadel/zitadel/security/advisories/GHSA-3gwm-5wx8-4gm6","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/zitadel-before-4.17.1-authentication-bypass-via-login-v2-otp-returncode","label":"disclosure@vulncheck.com"}],"tags":["nvd","cve.org"],"ingestedAt":"2026-10-04T15:00:34.390Z","slug":"CVE-2026-105211","body":"## Overview\n\nZITADEL 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.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":45,"depthScoreParts":{"impact":44.6,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}