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Vulnerability · Published Jul 19, 2026 · Assigned by Linux

CVE-2026-64073irq_work: Fix use-after-free in irq_work_single() on PREEMPT_RT

High 7.8

In plain English

A high-severity use-after-free in Linux from Linux. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.1% (higher than 3% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)7.8High
Exploit odds (30 days)0.1%top 97.2% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

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.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Debian:12linux6.1.176-1DEBIAN-CVE-2026-64073
Debian:13linux6.12.94-1DEBIAN-CVE-2026-64073
Debian:14linux7.0.12-1DEBIAN-CVE-2026-64073
Ubuntu:24.04:LTSlinux6.8.0-139.139UBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux6.8.0-139.139USN-8729-1
Ubuntu:26.04:LTSlinux7.0.0-28.28UBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-allwinner-5.19no fix listedUBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-aws6.8.0-1064.67UBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-aws6.8.0-1064.67USN-8729-6
Ubuntu:26.04:LTSlinux-aws7.0.0-1009.9UBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-aws-5.19no fix listedUBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-aws-6.14no fix listedUBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-aws-6.17no fix listedUBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-aws-6.2no fix listedUBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-aws-6.5no fix listedUBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-aws-6.86.8.0-1064.67~22.04.1USN-8729-6
Ubuntu:22.04:LTSlinux-aws-6.86.8.0-1064.67~22.04.1UBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-azure6.8.0-1067.75USN-8761-1
Ubuntu:24.04:LTSlinux-azure6.8.0-1067.75UBUNTU-CVE-2026-64073
Ubuntu:26.04:LTSlinux-azure7.0.0-1010.10UBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-azure-5.19no fix listedUBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-azure-6.11no fix listedUBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-azure-6.14no fix listedUBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-azure-6.17no fix listedUBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-azure-6.2no fix listedUBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-azure-6.5no fix listedUBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-azure-6.86.8.0-1067.75~22.04.1USN-8761-3
Ubuntu:22.04:LTSlinux-azure-6.86.8.0-1067.75~22.04.1UBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-azure-7.07.0.0-1014.14~24.04.1UBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-azure-fde6.8.0-1065.72UBUNTU-CVE-2026-64073
Ubuntu:26.04:LTSlinux-azure-fde7.0.0-1009.9UBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-azure-fde-5.19no fix listedUBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-azure-fde-6.14no fix listedUBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-azure-fde-6.17no fix listedUBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-azure-fde-6.2no fix listedUBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-azure-fde-6.86.8.0-1065.72~22.04.1UBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-azure-fde-7.07.0.0-1013.13~24.04.1UBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-azure-nvidiano fix listedUBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-azure-nvidia-6.14no fix listedUBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-gcp6.8.0-1067.75USN-8729-1
Ubuntu:24.04:LTSlinux-gcp6.8.0-1067.75UBUNTU-CVE-2026-64073
Ubuntu:26.04:LTSlinux-gcp7.0.0-1008.8UBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-gcp-5.19no fix listedUBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-gcp-6.11no fix listedUBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-gcp-6.14no fix listedUBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-gcp-6.17no fix listedUBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-gcp-6.2no fix listedUBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-gcp-6.5no fix listedUBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-gcp-6.86.8.0-1067.75~22.04.1UBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-gcp-6.86.8.0-1067.75~22.04.1USN-8729-3
Ubuntu:24.04:LTSlinux-gcp-7.07.0.0-1011.11~24.04.1UBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-gke6.8.0-1062.70USN-8729-1
Ubuntu:24.04:LTSlinux-gke6.8.0-1062.70UBUNTU-CVE-2026-64073
Ubuntu:26.04:LTSlinux-gke7.0.0-1003.4UBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-gkeop6.8.0-1049.53USN-8729-1
Ubuntu:24.04:LTSlinux-gkeop6.8.0-1049.53UBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-hwe-5.19no fix listedUBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-hwe-6.11no fix listedUBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-hwe-6.14no fix listedUBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-hwe-6.17no fix listedUBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-hwe-6.2no fix listedUBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-hwe-6.5no fix listedUBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-hwe-6.8no fix listedUBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-hwe-7.07.0.0-28.28~24.04.1UBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-ibm6.8.0-1064.65USN-8729-3
Ubuntu:24.04:LTSlinux-ibm6.8.0-1064.65UBUNTU-CVE-2026-64073
Ubuntu:26.04:LTSlinux-ibm7.0.0-1010.10UBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-ibm-6.86.8.0-1066.67~22.04.1UBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-intel-iot-realtimeno fix listedUBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-lowlatency6.8.0-139.139.1UBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-lowlatency6.8.0-139.139.1USN-8729-4
Ubuntu:22.04:LTSlinux-lowlatency-hwe-5.19no fix listedUBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-lowlatency-hwe-6.11no fix listedUBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.2no fix listedUBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.5no fix listedUBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.86.8.0-139.139.1~22.04.1UBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.86.8.0-139.139.1~22.04.1USN-8729-4
Ubuntu:24.04:LTSlinux-nvidia6.8.0-1062.65USN-8729-1
Ubuntu:24.04:LTSlinux-nvidia6.8.0-1062.65UBUNTU-CVE-2026-64073
Ubuntu:26.04:LTSlinux-nvidia7.0.0-1016.16UBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-nvidia-6.11no fix listedUBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-nvidia-6.17no fix listedUBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-nvidia-6.2no fix listedUBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-nvidia-6.5no fix listedUBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-nvidia-6.86.8.0-1062.65~22.04.1UBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-nvidia-6.86.8.0-1062.65~22.04.1USN-8729-1
Ubuntu:24.04:LTSlinux-nvidia-7.07.0.0-1016.16~24.04.1UBUNTU-CVE-2026-64073
Ubuntu:26.04:LTSlinux-nvidia-bos7.0.0-2016.16UBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-nvidia-lowlatency6.8.0-1062.65.1UBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-nvidia-lowlatency6.8.0-1062.65.1USN-8729-1
Ubuntu:24.04:LTSlinux-nvidia-tegra6.8.0-1035.38UBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-oem-5.17no fix listedUBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-oem-6.0no fix listedUBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-oem-6.1no fix listedUBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-oem-6.11no fix listedUBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-oem-6.14no fix listedUBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-oem-6.17no fix listedUBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-oem-6.5no fix listedUBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-oem-6.8no fix listedUBUNTU-CVE-2026-64073
Ubuntu:26.04:LTSlinux-oem-7.07.0.0-1009.9UBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-oracle6.8.0-1061.64UBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-oracle6.8.0-1061.64USN-8802-1
Ubuntu:26.04:LTSlinux-oracle7.0.0-1008.8UBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-oracle-6.14no fix listedUBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-oracle-6.17no fix listedUBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-oracle-6.5no fix listedUBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-oracle-6.86.8.0-1061.64~22.04.1UBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-oracle-6.86.8.0-1061.64~22.04.1USN-8802-1
Ubuntu:24.04:LTSlinux-oracle-7.07.0.0-1011.11~24.04.1UBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-raspi6.8.0-1064.68UBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-raspi6.8.0-1064.68USN-8729-1
Ubuntu:26.04:LTSlinux-raspi7.0.0-1015.15UBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-raspi-realtimeno fix listedUBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-realtimeno fix listedUBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-realtimeno fix listedUBUNTU-CVE-2026-64073
Ubuntu:26.04:LTSlinux-realtime7.0.0-28.28.1UBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-riscvno fix listedUBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-riscvno fix listedUBUNTU-CVE-2026-64073
Ubuntu:26.04:LTSlinux-riscv7.0.0-28.28.1UBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-riscv-5.19no fix listedUBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-riscv-6.14no fix listedUBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-riscv-6.17no fix listedUBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-riscv-6.5no fix listedUBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-riscv-6.86.8.0-139.139~22.04.1UBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-riscv-7.07.0.0-28.28.1~24.04.3UBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-starfive-5.19no fix listedUBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-starfive-6.2no fix listedUBUNTU-CVE-2026-64073
Ubuntu:22.04:LTSlinux-starfive-6.5no fix listedUBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-vmware6.8.0-1008.8UBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-xilinx6.8.0-1036.37UBUNTU-CVE-2026-64073
Ubuntu:24.04:LTSlinux-xilinx6.8.0-1036.37USN-8729-3

Affected products (as reported)

VendorProductVersions
Linux Linux 810979682ccc98dbd83f341c18a2e556c30a7164 – before 2dc79362302922cb18f35e262712b5e58de65442810979682ccc98dbd83f341c18a2e556c30a7164 – before eef4f71b46a9929ac33e968538c9dd5d96a02460810979682ccc98dbd83f341c18a2e556c30a7164 – before 684a78183c54c23e70d1cba320f7fc184604210b810979682ccc98dbd83f341c18a2e556c30a7164 – before 18c0456ea2615b1a743a6db739c74411c3b42bc6810979682ccc98dbd83f341c18a2e556c30a7164 – before 81b582784518196eff1050212a046bc29d3a05dd810979682ccc98dbd83f341c18a2e556c30a7164 – before 91840be8f710370607f949a627e070896faeddb8
Linux Linux 5.16

Weakness: CWE-416 · Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

References