CVE-2026-54088
File Browser: Command Injection via Authentication Hook Shell Substitution (Pre-Authentication RCE)
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
Description
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.
Public exploit
A reference of the record is tagged as an exploit or proof of concept: anyone can try it against an unpatched system. CISA's SSVC rates its exploitation: a proof of concept is public.
- https://github.com/filebrowser/filebrowser/security/advisories/GHSA-m93h-4hw7-5qcm (opens in a new tab)x_refsource_CONFIRMexploit
Timeline
ID reserved
By GitHub_M
- 14 days later
· 14 days later
Published
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 4.0 | Critical9.3 | 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 |
| NVDNVD · Deferred | 4.0 | Critical9.3 | 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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
- EPSS (exploitation in 30 days)
- 0.76% · top 44% of all CVEs (7 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.3.
Weakness
- CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') (opens in a new tab)All about CWE-78 and its CVEs
- CWE-88: Improper Neutralization of Argument Delimiters in a Command ('Argument Injection') (opens in a new tab)All about CWE-88 and its CVEs
- CWE-306: Missing Authentication for Critical Function (opens in a new tab)All about CWE-306 and its CVEs
Affected products
- affected < 2.63.6
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- Gogithub.com/filebrowser/filebrowser/v2GHSA-m93h-4hw7-5qcm (opens in a new tab)
References (1)
- https://github.com/filebrowser/filebrowser/security/advisories/GHSA-m93h-4hw7-5qcm (opens in a new tab)x_refsource_CONFIRMexploit
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-m93h-4hw7-5qcm (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-54088)Record last updated .