What is CVE-2026-121555?

CVE-2026-121555 is a high-severity vulnerability in Drizzletime Foxel, classified under Missing Authentication for Critical Function. CVSS score: 7.5/10. Published 2026-11-03.

How severe is CVE-2026-121555?

High severity. CVSS v3 base score is 7.5 out of 10.

Auth bypass in Drizzletime Foxel

CVE-2026-121555

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.

Vulnerability class: Broken Authentication

Published 2026-11-03 · last modified 2026-11-03.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Drizzletime Foxel

Weakness classification (CWE)

CWE-306 — Missing Authentication for Critical Function

References

github.com/DrizzleTime/Foxel/issues/152 (issue-tracking)
github.com/DrizzleTime/Foxel (product)
github.com/DrizzleTime/Foxel/commit/73d9fa825e1004d37abb7b10faea0cd7f5bcb463 (patch)
github.com/DrizzleTime/Foxel/blob/v2.4.0/domain/virtual_fs/api.py (technical-description)
github.com/DrizzleTime/Foxel/blob/v2.4.0/api/routers.py (technical-description)
www.vulncheck.com/advisories/foxel-through-2.4.0-unauthenticated-file-read-via-… (third-party-advisory)

Frequently asked questions

What is CVE-2026-121555?: CVE-2026-121555 is a high-severity vulnerability in Drizzletime Foxel, classified under Missing Authentication for Critical Function. CVSS score: 7.5/10. Published 2026-11-03.
How severe is CVE-2026-121555?: High severity. CVSS v3 base score is 7.5 out of 10.