CVE-2026-33179 (GCVE-0-2026-33179)
Vulnerability from cvelistv5 – Published: 2026-03-20 20:20 – Updated: 2026-03-25 13:55
VLAI
EPSS
VEX
Title
libfuse: NULL Pointer Dereference and Memory Leak in io_uring Queue Initialization
Summary
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.
Severity
5.5 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-25 13:55 UTC
CWE
- CWE-476 - NULL Pointer Dereference
Assigner
GitHub_M
CNA
References
3 references
| URL | Tags |
|---|---|
| https://github.com/libfuse/libfuse/security/advis… | x_refsource_CONFIRM |
| https://github.com/libfuse/libfuse/commit/7beb86c… | x_refsource_MISC |
| https://github.com/libfuse/libfuse/releases/tag/f… | x_refsource_MISC |
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