CVE-2026-80859
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 versions
Linux kernel versions
6.14
and later are affected. Fixed in
6.18.51,
7.2.3,
7.3
and their respective stable series.
References
3 totalFrequently asked questions
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What is CVE-2026-80859?
CVE-2026-80859 is a unscored severity Linux kernel vulnerability . It affects Linux kernel versions from 6.14 onward and has been patched in 6.18.51, 7.2.3 and 7.3. CVE-2026-80859 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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Is there a patch available for CVE-2026-80859?
Yes. CVE-2026-80859 has been patched. Fixed versions include 6.18.51, 7.2.3 and 7.3. If you are running Linux kernel 6.14 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2026-80859 actively exploited?
No. CVE-2026-80859 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.