Use-after-free in Linux kernel - CVE-2026-46317

CSH
CYBERSECURITY HELP
Sign In REGISTER
 
Main Vulnerability Database Vulnerabilities #VU134177

Use-after-free in Linux kernel - CVE-2026-46317

Published: June 10, 2026


Vulnerability identifier: #VU134177
CSH Severity: Low
CVSS v4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-46317
CWE-ID: CWE-416
Exploitation vector: Local access
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to a use-after-free in the nested_mmus array in arm64 KVM nested virtualization when reallocating nested MMU structures while the array is being walked under mmu_lock. A local user can trigger nested vcpu initialization and concurrent MMU notifier activity to cause a denial of service.

The issue arises from a race condition between nested vcpu initialization and the MMU notifier path.


Affected software

Linux kernel
Red Hat Enterprise Linux for ARM 64
Red Hat Enterprise Linux for Power, little endian
Red Hat Enterprise Linux for IBM z Systems
Red Hat Enterprise Linux for x86_64
Ubuntu
kernel (Red Hat package)
linux-azure-fde-6.17 (Ubuntu package)
linux-gcp-6.17 (Ubuntu package)
linux-oracle-6.17 (Ubuntu package)
linux-azure-6.17 (Ubuntu package)
linux-oem-6.17 (Ubuntu package)
linux-nvidia-6.17 (Ubuntu package)
linux (Ubuntu package)
linux-ibm (Ubuntu package)
linux-aws (Ubuntu package)
linux-oem-7.0 (Ubuntu package)
linux-azure (Ubuntu package)
linux-gcp-7.0 (Ubuntu package)
linux-oracle-7.0 (Ubuntu package)
linux-azure-7.0 (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-nvidia-bos (Ubuntu package)

How to mitigate CVE-2026-46317

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
kernel (Red Hat package) - update to 6.12.0-211.61.1.el10_2
linux-azure-fde-6.17 (Ubuntu package) - update to 6.17.0-1018.18~24.04.1
linux-gcp-6.17 (Ubuntu package) - addressed in versions 6.17.0-1018.20~24.04.1, 6.17.0-1021.24~24.04.1
linux-oracle-6.17 (Ubuntu package) - addressed in versions 6.17.0-1019.19~24.04.3, 6.17.0-1019.19~24.04.3+1
linux-azure-6.17 (Ubuntu package) - update to 6.17.0-1021.21~24.04.1
linux-oem-6.17 (Ubuntu package) - update to 6.17.0-1030.30
linux-nvidia-6.17 (Ubuntu package) - update to 6.17.0-1031.31
linux (Ubuntu package) - addressed in versions 7.0.0-28.28, 7.0.0-28.28.1, 7.0.0-1003.4, 7.0.0-1008.8
linux-ibm (Ubuntu package) - addressed in versions 7.0.0-1008.8, 7.0.0-1010.10
linux-aws (Ubuntu package) - addressed in versions 7.0.0-1009.9, 7.0.0-1015.15
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1009.9
linux-azure (Ubuntu package) - addressed in versions 7.0.0-1009.9, 7.0.0-1010.10
linux-gcp-7.0 (Ubuntu package) - update to 7.0.0-1011.11~24.04.1
linux-oracle-7.0 (Ubuntu package) - update to 7.0.0-1011.11~24.04.1
linux-azure-7.0 (Ubuntu package) - update to 7.0.0-1014.14~24.04.1
linux-nvidia (Ubuntu package) - addressed in versions 7.0.0-1016.16, 7.0.0-1016.16~24.04.1
linux-nvidia-bos (Ubuntu package) - update to 7.0.0-2016.16

External References

Related Security Bulletins