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TI-2026-39017 Aliases CVE-2026-54088GHSA-m93h-4hw7-5qcm

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

Priority HIGH 79CWE-306Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Security bypass, Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-306 and CWE-78.

Summary

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00764 55th percentileScored 2026-11-07
Fix Fixed filebrowser (filebrowser): 2.63.6github.com/filebrowser/filebrowser/v2 (Go): 2.63.6

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
filebrowserfilebrowserbefore 2.63.62.63.6Patch availableCNA
—github.com/filebrowser/filebrowser/v2 (Go)before 2.63.62.63.6Patch availableGHSA-m93h-4hw7-5qcm
  • filebrowser Vendorfilebrowser Affected before 2.63.6 Fixed in 2.63.6 Patch available CNA
  • github.com/filebrowser/filebrowser/v2 (Go) Vendor— Affected before 2.63.6 Fixed in 2.63.6 Patch available GHSA-m93h-4hw7-5qcm

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:filebrowser:filebrowser:*:*:*:*:*:*:*:*——filebrowser
  • cpe:2.3:a:filebrowser:filebrowser:*:*:*:*:*:*:*:* Versions — — ·filebrowser

Remediation

  • Fix · CNA filebrowser (filebrowser) Fixed in 2.63.6
  • Fix · GHSA-m93h-4hw7-5qcm github.com/filebrowser/filebrowser/v2 (Go) Fixed in 2.63.6 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-54088
  2. 2026-10-03 Alias added: GHSA-m93h-4hw7-5qcm

References

Advisory 1

Other 2

  • TI-2026-25251 File Browser Self Registration Grants Any User Admin Access When Default Permissions Include Admin CVSS 4.0CRITICAL 10.0
  • TI-2026-51065 filebrowser through 2.63.16 Privilege Escalation via Signup CVSS 4.0CRITICAL 9.3
  • TI-2026-39018 File Browser: Authentication Bypass via Proxy Auth Header Forgery CVSS 3.1CRITICAL 9.1
  • TI-2026-23305 File Browser: TUS Delete Endpoint Bypasses Delete Permission Check CVSS 3.1CRITICAL 9.1
  • TI-2026-26777 File Browser's Signup Grants Execution Permissions When Default Permissions Includes Execution CVSS 3.1CRITICAL 9.8
  • TI-2025-33000 File Browser vulnerable to command execution allowlist bypass CVSS 3.1HIGH 8.1
See all 64 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences