CVE-2026-80859: Linux

EPSS: 0.2% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: fuse: fix missing barrier when checking io-uring readiness fuse_block_alloc() reads fch->initialized and then fch->io_uring. fch->io_uring is set before fch->initialized, ordered by the smp_wmb() in fuse_chan_set_intialized(), but fuse_block_alloc() has no matching read barrier between the two loads. This may lead a CPU to observe fch->initialized=1 but fch->io_uring=0, and skip the check that blocks request allocation until the io-uring queues are ready. This can reintroduce the lock-order inversion deadlock that commit 3393ff964e0f prevents. Add an smp_rmb() barrier to pair with the smp_wmb() in fuse_chan_set_initialized() to prevent this.

Affected products

• Linux Linux: from 6.14, before 6.18.51 (fixed in 6.18.51); from 6.19, before 7.2.3 (fixed in 7.2.3)

Published 2026-09-04. Last modified 2026-09-11.