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PatchSiren cyber security CVE debrief

CVE-2026-54910 gtsteffaniak CVE debrief

CVE-2026-54910 is a high-severity path traversal vulnerability in FileBrowser Quantum, a free, self-hosted, web-based file manager. An attacker can exploit this vulnerability to read any text file readable by the server process, potentially leading to unauthorized access to sensitive data. The vulnerability is caused by the `subtitlesHandler` endpoint accepting two user-controlled query parameters, `path` and `name`, which are used in filesystem operations without sanitization. This creates two independent path traversal vectors, allowing an attacker to escape the storage root and read any text file readable by the server process.

Vendor
gtsteffaniak
Product
filebrowser
CVSS
HIGH 7.7
CISA KEV
Not listed in stored evidence
Original CVE published
2026-07-20
Original CVE updated
2026-07-20
Advisory published
2026-07-20
Advisory updated
2026-07-20

Who should care

Users of FileBrowser Quantum, especially those with sensitive data stored on the server, should be aware of this vulnerability and take immediate action to patch their installations. System administrators and security teams responsible for managing FileBrowser Quantum installations should prioritize patching and monitor server logs for suspicious activity.

Technical summary

The `subtitlesHandler` endpoint in FileBrowser Quantum accepts two user-controlled query parameters, `path` and `name`, which are used in filesystem operations without sanitization. This creates two independent path traversal vectors, allowing an attacker to escape the storage root and read any text file readable by the server process. The primary vector is the `path` parameter, which is passed directly to `idx.GetRealPath()` without calling `SanitizeUserPath()`. The secondary vector is the `name` parameter, which is joined with `parentDir` via `filepath.Join(parentDir, name)` without stripping directory components.

Defensive priority

High

Recommended defensive actions

  • Apply the patch from version 1.4.3-beta or later
  • Restrict access to the `subtitlesHandler` endpoint
  • Monitor server logs for suspicious activity
  • Implement additional security measures, such as Web Application Firewalls (WAFs)
  • Conduct regular vulnerability assessments and penetration testing
  • Review compensating controls for exposed systems while remediation is scheduled and verified
  • Track exceptions, retest remediated assets, and close the item only after evidence is documented

Evidence notes

The CVE record was published on 2026-07-20T15:16:43.933Z and last modified on 2026-07-20T16:17:05.233Z. The NVD entry is currently 7.7 HIGH. The vulnerability affects FileBrowser Quantum, a free, self-hosted, web-based file manager. Evidence of exploitation is limited, and defenders should verify the patch status of their installations. No public exploits are known, but defenders should monitor server logs for suspicious activity.

Official resources

AI-assisted PatchSiren debrief based on the supplied source corpus. The CVE record was published on 2026-07-20T15:16:43.933Z and has not been modified since then. The NVD entry is currently 7.7 HIGH.