CVE-2026-54091 File Browser: Incorrect access control in public directory shares via rule path rebasing
An attacker can access blocked files in public directory shares due to incorrect path rebasing in access control rules, leading to information disclosure.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-54091?
CVE-2026-54091 is a high-severity missing authorization vulnerability in filebrowser, published on 25 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
File Browser is a file managing interface for uploading, deleting, previewing, renaming, and editing files within a specified directory. Prior to 2.63.6, File Browser's public share handlers rebase the share owner's filesystem root to the shared directory and then evaluate descendant paths against the owner's global and per-user rules using the rebased relative path instead of the original path relative to the owner's scope. As a result, an attacker who knows a public directory share URL can access files and subdirectories that the owner explicitly blocked with rules, as long as those blocked paths are located underneath the shared directory. In the simplest case this is an unauthenticated information disclosure through `GET /api/public/share/*` and `GET /api/public/dl/*`. This vulnerability is fixed in 2.63.6.
Weakness: CWE-863
Which versions are affected by CVE-2026-54091?
4 open source packages ship an affected version, including github.com/filebrowser/filebrowser/v2 and github.com/filebrowser/filebrowser.
| Package | Affected | Fixed in |
|---|---|---|
github.com/filebrowser/filebrowser/v2 Go | All versions | 2.63.6 |
github.com/filebrowser/filebrowser/v2 Go | All versions | 2.63.6 |
github.com/filebrowser/filebrowser/v2 Go | All versions | 2.63.6 |
github.com/filebrowser/filebrowser Go | All versions | None |
How do I fix CVE-2026-54091?
Upgrade github.com/filebrowser/filebrowser/v2 to 2.63.6 or later.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-54091 being exploited?
There is no known exploitation of CVE-2026-54091 in the wild and no public exploit code.
Sources
Also known as GHSA-j9jx-hp4c-ghhh, GO-2026-5458.