CVE-2026-54089 Details
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.
A vulnerability in File Browser versions 2.0.0-rc.1 and later, when configured to use proxy authentication, allows unauthenticated attackers to impersonate any user, including administrators. This is achieved by sending a single forged HTTP header, without the need for credentials. Additionally, the vulnerability enables the creation of new user accounts by specifying a non-existent username, bypassing authorization requirements. The issue arises because the application trusts headers from any source without validation, relying solely on network isolation, which can be easily circumvented.
To address this vulnerability, it is recommended to add validation for trusted proxy IPs, make automatic user creation an opt-in feature, and update documentation to warn users about the risks of exposing File Browser directly to untrusted networks.
Metrics
CVSS 4.0 Severity and Vector Strings:
VolerionCVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
Volerion
Assessed Jun 25, 2026CISA-ADP
Assessed Jun 25, 2026References to Advisories, Solutions, and Tools
By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.
| URL | Source(s) | Tag(s) |
|---|---|---|
| https://github.com/filebrowser/filebrowser/security/advisories/GHSA-xqp3-jq6g-x3qm | CISA-ADP | AdvisoryExploitRemedyVendor |
| https://github.com/filebrowser/filebrowser/blob/main/auth/proxy.go | [email protected] | Broken LinkSource CodeVendor |
| https://github.com/filebrowser/filebrowser/blob/main/http/auth.go#L121-L137 | [email protected] | Broken LinkSource CodeVendor |
| https://github.com/filebrowser/filebrowser/security/advisories/GHSA-xqp3-jq6g-x3qm | [email protected] | AdvisoryExploitRemedyVendor |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-287 | Improper Authentication | [email protected] |
| CWE-290 | Authentication Bypass by Spoofing | [email protected] |
Affected Products
| Product | Versions |
|---|---|
| FileBrowser | ~2.0.0-rc.1 (semver) |
CPE
Remediation
| |
Change History
2 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Jun 25, 2026 | New CVE Received | [email protected] |
| Jun 25, 2026 | CVE Modified | CISA-ADP |