{"id":"CVE-2026-89022","title":"BookStack before 26.05.5 contains an authentication bypass vulnerability in its social login implementation that allows unauthenticated attackers to sign in as arbitrary users by authenticating through a different social provider sharing…","summary":"BookStack before 26.05.5 contains an authentication bypass vulnerability in its social login implementation that allows unauthenticated attackers to sign in as arbitrary users by authenticating through a different social provider sharing…","severity":"high","cvss":7.4,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","cwe":["CWE-290"],"vendor":"bookstackapp","product":"bookstack","affected":["bookstack < 26.05.5"],"published":"2026-09-15","updated":"2026-09-16","sourceUpdated":"2026-09-16T19:47:01.197","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-89022","references":[{"url":"https://www.bookstackapp.com/blog/bookstack-release-v26-05-5/","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/bookstack-authentication-bypass-via-social-login-provider-confusion","label":"disclosure@vulncheck.com"}],"tags":["nvd","cve.org"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-09-15T19:04:04.179125Z"},"ingestedAt":"2026-09-15T16:40:03.398Z","epss":0.00288,"epssPercentile":0.21499,"slug":"CVE-2026-89022","body":"## Overview\n\nBookStack before 26.05.5 contains an authentication bypass vulnerability in its social login implementation that allows unauthenticated attackers to sign in as arbitrary users by authenticating through a different social provider sharing the same driver_id namespace. Attackers can authenticate at one enabled social provider using a user ID that matches an account linked to a different social provider, bypassing credential verification entirely because the SocialAuthService::handleLoginCallback query ignores the driver column when retrieving linked account records.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":40.7,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}