Use-after-free in libfuse - CVE-2026-33150
Published: April 25, 2026
Vulnerability identifier: #VU127891
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-33150
CWE-ID: CWE-416
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: libfuse
Affected software:
libfuse
libfuse
Detailed vulnerability description
The vulnerability allows a local user to execute arbitrary code.
The vulnerability exists due to use-after-free in the io_uring subsystem of libfuse when io_uring thread creation fails and the session later shuts down. A local user can trigger resource exhaustion that causes thread creation to fail to execute arbitrary code.
The issue can also crash FUSE filesystem processes using the io_uring transport on session shutdown. The io_uring transport must be explicitly enabled, and the trigger is reliable in containerized environments where cgroup pids.max limits constrain thread creation.
How to mitigate CVE-2026-33150
Install security update from vendor's website.