Medium severity · published Mar 20, 2026
CVE-2026-33179
libfuse: NULL Pointer Dereference and Memory Leak in io_uring Queue Initialization
5.5
CVSS
0.2%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 10% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
libfuse · libfuse
>= 3.18.0, < 3.18.2 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-33179
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-33179
Patch
https://github.com/libfuse/libfuse/commit/7beb86c09b6ec5aab14dc25256ed8a5ad18554d7
Product
https://github.com/libfuse/libfuse/releases/tag/fuse-3.18.2
Vendor Advisory
https://github.com/libfuse/libfuse/security/advisories/GHSA-x669-v3mq-r358
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