CVE-2026-33179
MEDIUMlibfuse: NULL Pointer Dereference and Memory Leak in io_uring Queue Initialization
Title source: cnaDescription
libfuse is the reference implementation of the Linux FUSE. From version 3.18.0 to before version 3.18.2, a NULL pointer dereference and memory leak in fuse_uring_init_queue allows a local user to crash the FUSE daemon or cause resource exhaustion. When numa_alloc_local fails during io_uring queue entry setup, the code proceeds with NULL pointers. When fuse_uring_register_queue fails, NUMA allocations are leaked and the function incorrectly returns success. Only the io_uring transport is affected; the traditional /dev/fuse path is not affected. PoC confirmed with AddressSanitizer/LeakSanitizer. This issue has been patched in version 3.18.2.
References (3)
Core 3
Core References
X_Refsource_Confirm x_refsource_confirm
https://github.com/libfuse/libfuse/security/advisories/GHSA-x669-v3mq-r358
X_Refsource_Misc x_refsource_misc
https://github.com/libfuse/libfuse/commit/7beb86c09b6ec5aab14dc25256ed8a5ad18554d7
X_Refsource_Misc x_refsource_misc
https://github.com/libfuse/libfuse/releases/tag/fuse-3.18.2
Scores
CVSS v3
5.5
EPSS
0.0020
EPSS Percentile
9.5%
Attack Vector
LOCAL
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
partial
Details
CWE
CWE-476
Status
published
Products (2)
libfuse/libfuse
>= 3.18.0, < 3.18.2
libfuse_project/libfuse
3.18.0 - 3.18.2
Published
Mar 20, 2026
Tracked Since
Mar 21, 2026