TI-2026-39019 Aliases CVE-2026-54090 GHSA-8c9q-7855-wfxq

File Browser: Command Allowlist Bypass via Shell Metacharacter Injection

HIGH 73CWE-184Published 2026-06-25 · Updated 2026-06-26

Key facts

Attack vector: Network
Privileges required: Low
User interaction: None
Attack complexity: Low
Attack requirements: None
Impact type: 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-77.

Summary

File Browser is a file managing interface for uploading, deleting, previewing, renaming, and editing files within a specified directory. Prior to 2.33.8, when a shell interpreter is configured (e.g. /bin/sh -c), the command allowlist can be bypassed through shell metacharacters. The allowlist validates only the first token of user input, but the entire raw string is handed to the shell — semicolons, pipes, backticks, and $() all work to chain arbitrary commands after a permitted one. This vulnerability is fixed in 2.33.8.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV

EPSS 0.00437 38th percentileScored 2026-11-07

Fix Fixed filebrowser (filebrowser): 2.33.8github.com/filebrowser/filebrowser/v2 (Go): 2.33.8

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: Poc
Automatable: No
Technical impact: Total

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

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
filebrowser	filebrowser	before 2.33.8	2.33.8	Patch available	CNA
—	github.com/filebrowser/filebrowser/v2 (Go)	before 2.33.8	2.33.8	Patch available	GHSA-8c9q-7855-wfxq

filebrowser Vendorfilebrowser Affected before 2.33.8 Fixed in 2.33.8 Patch available CNA
github.com/filebrowser/filebrowser/v2 (Go) Vendor— Affected before 2.33.8 Fixed in 2.33.8 Patch available GHSA-8c9q-7855-wfxq

CPE names Threatist (inferred) · 1

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

CPE	Versions	Role	Vendor
cpe:2.3:a:filebrowser:filebrowser::::::::	—	—	filebrowser

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

Remediation

Fix · CNA filebrowser (filebrowser) Fixed in 2.33.8
Fix · GHSA-8c9q-7855-wfxq github.com/filebrowser/filebrowser/v2 (Go) Fixed in 2.33.8 Advisory →

Timeline

2026-10-02 Threatist record created from CVE-2026-54090
2026-10-03 Alias added: GHSA-8c9q-7855-wfxq

References

Advisory 1

https://nvd.nist.gov/vuln/detail/CVE-2026-54090

Other 3

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-2026-39017 File Browser: Command Injection via Authentication Hook Shell Substitution (Pre-Authentication RCE) CVSS 4.0CRITICAL 9.3
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

See all 64 →

Sources

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