SB20261023241 - Use-after-free in Linux kernel arm64 kvm

Description

This security bulletin contains information about 1 vulnerability.

1) Use-after-free (CVE-ID: CVE-2026-98927)

CWE-ID: CWE-416 - Use After Free

CVSSv4: 5.7 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

The vulnerability allows a local user to potentially cause a denial of service through a kernel crash.

The vulnerability exists due to use-after-free in the Linux kernel arm64 KVM nested virtualization component when VCPU_INIT relocates the nested_mmus array while a vCPU is running an L2 guest. A local user can trigger concurrent vCPU initialization and nested guest execution to potentially cause a denial of service by leaving the running vCPU accessing a freed shadow page table structure.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/33346f8960c7bb6a3b4e273b5cfe25c5a8be349f
• https://git.kernel.org/stable/c/512c93f4461b9a3735987f48423d438a9cd49e6a
• https://git.kernel.org/stable/c/81e3f065a6485626f816d791dfd5e00ddd12eff5
• https://git.kernel.org/stable/c/ea242bdc29e8a8ff0e2447a64b3841114779f3af