{"schemaVersion":3,"id":"CVE-2026-109373","aliases":[],"status":"published","duplicateOf":null,"title":null,"description":"ZITADEL 3.0.0 before 4.19.2 contains an authentication bypass vulnerability in the Login V2 UI that allows unauthenticated attackers to obtain other users' session tokens by forging unsigned session cookies. 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This causes the product to appear to be the source of the request, leading it to act as a proxy or other intermediary between the upstream component and the external actor.","type":"weakness","status":"Draft","abstraction":"Class","likelihoodOfExploit":null,"url":"https://cwe.mitre.org/data/definitions/441.html"}],"affected":[{"vendor":"zitadel","product":"zitadel","name":"zitadel","label":"zitadel","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"≥ 3.0.0, < 4.19.2","noFixRecorded":false,"fixedIn":null}],"versionsText":"≥ 3.0.0, < 4.19.2","eol":null,"hubHref":"/vendor/zitadel/zitadel"}],"affectedCount":1,"eol":{"hasEol":false,"count":0},"references":[{"url":"https://github.com/zitadel/zitadel/security/advisories/GHSA-jh92-5mrj-p2w2","label":"github.com/zitadel/zitadel/security/advisories/GHSA-jh92-5mrj-p2w2","hostname":"github.com","tags":["Vendor Advisory"]},{"url":"https://www.vulncheck.com/advisories/zitadel-3.0.0-before-4.19.2-account-takeover-via-unsigned-login-v2-session-cookie","label":"www.vulncheck.com/advisories/…","hostname":"www.vulncheck.com","tags":["Third Party Advisory"]}],"lineage":{"upstream":[],"downstream":[],"duplicates":[],"related":[]},"timeline":[{"kind":"published","date":"2026-10-12T16:05:45.649Z","label":"Published","detail":"Vulnerability first disclosed.","source":null},{"kind":"modified","date":"2026-10-13T16:53:01.016Z","label":"Last modified","detail":"Vulnerability information updated.","source":null}],"risk":{"score":70,"level":"high","profile":"Default","thresholds":{"critical":75,"high":50,"medium":25,"low":10}},"meta":{"dataAsOf":"2026-10-21T02:39:36.989Z","stale":false,"partial":false}}