CVE-2026-54089

critical

Description

File Browser is a file managing interface for uploading, deleting, previewing, renaming, and editing files within a specified directory. Starting with 2.0.0-rc.1, when FileBrowser is configured with proxy authentication (auth.method=proxy), any unauthenticated attacker who can reach the server directly can impersonate any user - including admin - by sending a single forged HTTP header. No credentials are required. Additionally, specifying a non-existent username causes the server to automatically create a new user account, providing an account creation primitive with no authorization. This is an already known issue that has been documented in the documentation for several years, but has not been documented as a vulnerability before.

References

https://github.com/filebrowser/filebrowser/security/advisories/GHSA-xqp3-jq6g-x3qm

https://github.com/filebrowser/filebrowser/blob/main/http/auth.go#L121-L137

https://github.com/filebrowser/filebrowser/blob/main/auth/proxy.go

Details

Source: Mitre, NVD

Published: 2026-06-25

Updated: 2026-06-25

Risk Information

CVSS v2

Base Score: 9.4

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:N

Severity: High

CVSS v3

Base Score: 9.1

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Severity: Critical

EPSS

EPSS: 0.00042