CVE-2026-121555

High CVSS 7.5

Published 2026-11-03 · last changed 2026-11-03

The fix

We hold no Microsoft remediation data for CVE-2026-121555, which normally means it is not a Windows CVE. For non-Microsoft software the fix is the vendor's own updated release, and the affected versions are listed below.

What it is

Foxel through 2.4.0 contains a missing authentication vulnerability that allows unauthenticated attackers to read files by requesting the /api/fs/stream and /api/fs/thumb endpoints. Attackers can supply a VFS mount prefix and relative path to retrieve full file contents or thumbnails across all mounts, bypassing PathRule permission grants.

Sources

NVD record for CVE-2026-121555

CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N