Description
filebrowser versions before v2.63.21 fail to canonicalize paths before evaluating access rules, allowing authenticated users to bypass administrator-defined deny rules using case-variant or backslash-separated paths. Attackers can request files with alternate path representations that match no rule but resolve to the same filesystem object, gaining unauthorized access to denied files within their scope.
References3
Metrics
- CVSS 3.1
-
6.8
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N - CVSS 4.0
-
7.6
HIGH
Score source: CNA
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/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:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 43 · as of 12 November 2026
- CWE
- CWE-41
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