CVE-2026-54091: File Browser incorrect authorization in public directory shares

CVE-2026-54091 · Severity: high · CVSS 7.5 · Published 2026-06-25

File Browser, a web-based file management interface, contains a security flaw in how it handles public file sharing. An attacker who obtains a public share link can bypass security rules set by the owner to access restricted files or folders located within the shared directory. This could lead to the unauthorized disclosure of sensitive data, such as private documents or configuration files, without requiring a password or account.

Technologies: File Browser, github.com/filebrowser/filebrowser (Go), github.com/filebrowser/filebrowser/v2 (Go). Vendors: File Browser, Go.

Quick answers

Is CVE-2026-54091 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-54091 being exploited in the wild.
How severe is CVE-2026-54091?
High severity, with a CVSS score of 7.5, published 25 June 2026.
Which products and versions are affected?
File Browser < 2.63.6, <= 1.11.0; github.com/filebrowser/filebrowser (Go) <= 1.11.0, SEMVER:introduced=0; github.com/filebrowser/filebrowser/v2 (Go) <= 2.63.5, SEMVER:introduced=0,fixed=2.63.6.
Is there a fix for CVE-2026-54091?
Yes. github.com/filebrowser/filebrowser/v2 (Go): upgrade to 2.63.6 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-54091 attacked?
It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-54091?
Check whether you run File Browser, github.com/filebrowser/filebrowser (Go) or github.com/filebrowser/filebrowser/v2 (Go) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • github.com/filebrowser/filebrowser/v2 (Go): upgrade to 2.63.6 or later
    go get github.com/filebrowser/filebrowser/v2@v2.63.6

Technical details

An incorrect authorization vulnerability (CWE-863) exists in File Browser's public share handlers. When a directory is shared publicly, the application rebases the filesystem root to that directory but evaluates access rules using the new relative path instead of the original absolute path. Because the owner's 'deny' rules are typically defined relative to the original root, they fail to match the rebased paths (e.g., a rule blocking '/projects/private' will not match a request for '/private' within a share rooted at '/projects'). An unauthenticated attacker with a valid share URL can exploit this via the `/api/public/share/*` and `/api/public/dl/*` endpoints to read files or list directories that should be restricted. This issue is resolved in version 2.63.6.

Affected products

  • filebrowser File Browser < 2.63.6

Identifiers

  • CVE-2026-54091
  • GHSA-j9jx-hp4c-ghhh
  • GO-2026-5458

Timeline

  • 2026-06-03: patched: Version 2.63.6 released
  • 2026-06-06: advisory: GitHub Security Advisory published
  • 2026-06-25: disclosed: CVE published to NVD

References

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