CVE-2026-54088criticalCWE-306 CWE-78 CWE-88

CVE-2026-54088: critical vulnerability in filebrowser

File Browser: Command Injection via Authentication Hook Shell Substitution (Pre-Authentication RCE)

Published 25 Jun 2026

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48Vexday Risk Score

No sign of exploitation. It has a public proof of concept.

ssvc Attendcvss 9.3epss 0.8%

from disclosure to weaponsame day

Published on NVDJun 25

1st PoCJun 3

File Browser is a file managing interface for uploading, deleting, previewing, renaming, and editing files within a specified directory. Prior to 2.63.6, the Hook Authentication feature in File Browser allows administrators to delegate login verification to an external shell command. User-supplied credentials (username and password) are interpolated into this command string using os.Expand without sanitization. An unauthenticated remote attacker can inject shell metacharacters in the username or password field at the login screen, causing the server to execute arbitrary OS commands before any authentication takes place. This is a critical pre-authentication RCE. This vulnerability is fixed in 2.63.6.

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Affected products

filebrowser · filebrowser

public PoCs found — 1

githubgithub.com/Saku0512/CVE-2026-54088-poc★ 1

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