Use-after-free in Linux kernel - CVE-2026-64286

 

Use-after-free in Linux kernel - CVE-2026-64286

Published: July 27, 2026


Vulnerability identifier: #VU139698
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-2026-64286
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 improper handling of a stale pointer in flush_hyp_vcpu() when copying the host vCPU context into the hyp private vCPU. A local user can provide a crafted __hyp_running_vcpu value to cause a denial of service.

The issue occurs on arm64 KVM with pKVM at EL2 during vCPU context handling.


Affected software

Linux kernel
Debian Linux
linux (Debian package)

How to mitigate CVE-2026-64286

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
linux (Debian package) - update to 6.12.100-1

External References

Related Security Bulletins