CVE-2026-33150

high

Description

libfuse is the reference implementation of the Linux FUSE. From version 3.18.0 to before version 3.18.2, a use-after-free vulnerability in the io_uring subsystem of libfuse allows a local attacker to crash FUSE filesystem processes and potentially execute arbitrary code. When io_uring thread creation fails due to resource exhaustion (e.g., cgroup pids.max), fuse_uring_start() frees the ring pool structure but stores the dangling pointer in the session state, leading to a use-after-free when the session shuts down. The trigger is reliable in containerized environments where cgroup pids.max limits naturally constrain thread creation. This issue has been patched in version 3.18.2.

References

https://github.com/libfuse/libfuse/security/advisories/GHSA-qxv7-xrc2-qmfx

https://github.com/libfuse/libfuse/releases/tag/fuse-3.18.2

https://github.com/libfuse/libfuse/commit/49fcd891a58f622c098e2ca67d66086f7b213836

Details

Source: Mitre, NVD

Published: 2026-03-20

Updated: 2026-03-20

Risk Information

CVSS v2

Base Score: 6.8

Vector: CVSS2#AV:L/AC:L/Au:S/C:C/I:C/A:C

Severity: Medium

CVSS v3

Base Score: 7.8

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

Severity: High

EPSS

EPSS: 0.00012