CVE-2026-64073

CVE CVE-2026-64073EUVD EUVD-2026-45646Published 2026-07-19T15:39:48.000ZLast changed 2026-08-05T12:38:54.000ZCVSS 7.8

What the advisory describes

In the Linux kernel, the following vulnerability has been resolved: irq_work: Fix use-after-free in irq_work_single() on PREEMPT_RT On PREEMPT_RT, non-HARD irq_work runs in per-CPU kthreads via run_irq_workd(), so irq_work_sync() uses rcuwait() to wait for BUSY==0. After irq_work_single() clears BUSY via atomic_cmpxchg(), it still dereferences @work for irq_work_is_hard() and rcuwait_wake_up(). An irq_work_sync() caller on another CPU that enters after BUSY is cleared can observe BUSY==0 immediately, return, and free the work before those accesses complete — causing a use-after-free. Fix this by wrapping run_irq_workd() in guard(rcu)() so that the entire irq_work_single() execution is within an RCU read-side critical section. Then add synchronize_rcu() in irq_work_sync() after rcuwait_wait_event() to ensure the caller waits for the RCU grace period before returning, preventing premature frees.

Source: EUVD (ENISA), in the words of the advisory.

Products the advisory names

These come from the advisory itself, not from any check we performed.

Linux — Linux 810979682ccc98dbd83f341c18a2e556c30a7164 <684a78183c54c23e70d1cba320f7fc184604210b; patch: 6.12.92; patch: 6.18.34; patch: 0; 5.16; 810979682ccc98dbd83f341c18a2e556c30a7164 <eef4f71b46a9929ac33e968538c9dd5d96a02460; patch: 7.0.11; 810979682ccc98dbd83f341c18a2e556c30a7164 <2dc79362302922cb18f35e262712b5e58de65442; 810979682ccc98dbd83f341c18a2e556c30a7164 <18c0456ea2615b1a743a6db739c74411c3b42bc6; 810979682ccc98dbd83f341c18a2e556c30a7164 <91840be8f710370607f949a627e070896faeddb8; patch: 7.1; patch: 6.1.175; 810979682ccc98dbd83f341c18a2e556c30a7164 <81b582784518196eff1050212a046bc29d3a05dd; patch: 6.6.142

The versions shown are the advisory's own. Patchlage compares no version numbers and derives no judgement from them — which version is installed is something a person has to look up.

Carried in the product catalogue

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Linux — Linux

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