---
id: CVE-2026-72835
title: >-
  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
summary: >-
  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 reques…
severity: medium
cvss: 6.8
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N'
cwe:
  - CWE-41
published: '2026-08-14'
updated: '2026-09-08'
sourceUpdated: '2026-09-08T20:32:39.347'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-72835'
references:
  - url: >-
      https://github.com/filebrowser/filebrowser/security/advisories/GHSA-fgm5-pw99-w2p7
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/filebrowser-before-access-rule-bypass-via-path-canonicalization
    label: disclosure@vulncheck.com
  - url: >-
      https://github.com/filebrowser/filebrowser/security/advisories/GHSA-fgm5-pw99-w2p7
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
epss: 0.005
epssPercentile: 0.40264
ingestedAt: '2026-09-08T21:11:12.278Z'
---

## Overview

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.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.