{"id":"CVE-2026-72836","state":"PUBLISHED","title":"FileBrowser before 2.63.19 Case Sensitivity Authentication Bypass","description":"FileBrowser before 2.63.19 does not account for case-insensitive filesystems when checking home directory ownership during self-registration. When Signup and CreateUserDir are enabled and FileBrowser's root is on a case-insensitive filesystem (confirmed on Windows/NTFS), two self-registered usernames that differ only in letter case (e.g., CaseVictim and casevictim) are stored as distinct accounts but resolve to the same physical home directory, because the scope-ownership check compares the persisted scope as an exact case-sensitive string. A second registrant can therefore read, overwrite, and delete another account's files through authenticated HTTP endpoints, without needing an existing account or victim interaction.","publishedAt":"2026-08-14T11:35:41.491Z","updatedAt":"2026-08-18T02:00:53.619Z","severity":{"score":9.2,"label":"Critical","version":"4.0","vector":"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","source":"VulnCheck"},"assigner":"VulnCheck","products":["filebrowser filebrowser"],"affected":[{"vendor":"filebrowser","product":"filebrowser","packageURL":"pkg:golang/github.com/filebrowser/filebrowser/v2","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThan":"2.63.19","versionType":"semver"},{"version":"2.63.19","status":"unaffected","versionType":"semver"}]}],"references":["https://github.com/filebrowser/filebrowser/security/advisories/GHSA-576v-w77m-gr84","https://github.com/filebrowser/filebrowser/commit/fe7efb2e6afe66774cd86a5b0a03033bd514d0c0","https://www.vulncheck.com/advisories/filebrowser-before-case-sensitivity-authentication-bypass"],"weaknesses":["CWE-178"],"ingestedAt":"2026-10-29T20:12:58.252Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/72xxx/CVE-2026-72836.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-72836","state":"PUBLISHED","datePublished":"2026-08-14T11:35:41.491Z","dateUpdated":"2026-08-18T02:00:53.619Z","assignerShortName":"VulnCheck","assignerOrgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","dateReserved":"2026-08-10T15:13:41.486Z"},"containers":{"cna":{"title":"FileBrowser before 2.63.19 Case Sensitivity Authentication Bypass","descriptions":[{"lang":"en","value":"FileBrowser before 2.63.19 does not account for case-insensitive filesystems when checking home directory ownership during self-registration. 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