CVE-2026-54089: critical vulnerability in filebrowser
File Browser: Authentication Bypass via Proxy Auth Header Forgery
Published
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
28Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 9.1epss 0.6%
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Affected products
filebrowser · filebrowserRelated CVEs — filebrowser
In the same product, most dangerous first.
CVE-2026-35585HIGHFile Browser has a Command Injection via Hook RunnerEPSS 2.0%CVE-2026-32759MEDIUMFile Browser TUS Negative Upload-Length Fires Post-Upload Hooks PrematurelyEPSS 2.0%CVE-2025-52903HIGHFile Browser Allows Execution of Shell Commands That Can Spawn Other CommandsEPSS 1.2%CVE-2025-52904HIGHFile Browser: Command Execution not Limited to ScopeEPSS 1.1%CVE-2026-54088CRITICALFile Browser: Command Injection via Authentication Hook Shell Substitution (Pre-Authentication RCE)EPSS 0.8%CVE-2026-32760CRITICALFile Browser Self Registration Grants Any User Admin Access When Default Permissions Include AdminEPSS 0.7%