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Vulnerability record · CVE-2026-72836 · published 14 August 2026

CVE-2026-72836: FileBrowser before 2.63.19 does not account for case-insensitive filesystems when checking home directory owne…

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.

9.2 CVSS 4.0 Critical EPSS 0.55% · top 56.3% CWE-178 · CWE-178 Deferred
9.2CVSS 4.0 base score
0.55%EPSS exploitation probability, 30 days
NoNot in CISA KEV
0Affected product versions listed by NVD
4References
8 Sep 2026Last modified by NVD

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.

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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:

References

LinkTags
https://github.com/filebrowser/filebrowser/commit/fe7efb2e6afe66774cd86a5b0a03033bd514d0c0
https://github.com/filebrowser/filebrowser/security/advisories/GHSA-576v-w77m-gr84
https://www.vulncheck.com/advisories/filebrowser-before-case-sensitivity-authentication-bypass
https://github.com/filebrowser/filebrowser/security/advisories/GHSA-576v-w77m-gr84

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2026-72836), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.