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.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| libfuse | libfuse | >= 3.18.0, < 3.18.2 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | fuse3 | 3.18.2-1 | — |
Advisories 1
- WID-SEC-2026-0913 Red Hat FUSE (libfuse): Mehrere Schwachstellen ermöglichen Codeausführung und DoS BSI CERT-Bund (WID) · Apr 19, 2026