SB2026091751 - Race condition in Linux kernel arm64 kvm

Description

This security bulletin contains information about 1 vulnerability.

1) Race condition (CVE-ID: CVE-2026-89916)

CWE-ID: CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

CVSSv4: 8.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]

The vulnerability allows a remote attacker to disclose information, modify data, or cause a denial of service.

The vulnerability exists due to a race condition in KVM arm64 VNCR TLB handling when concurrently translating VNCR and invalidating stage 1 page-table entries. A remote attacker can trigger concurrent VNCR translation and stage 1 page-table invalidation to disclose information, modify data, or cause a denial of service.

A stale VNCR TLB entry can be inserted after the corresponding page-table entry has been invalidated.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/11ee3faab4f1755d126bead9f882e75a7a677860
• https://git.kernel.org/stable/c/2b7324f3a0c1072b9d578b8d42f199506753f26e
• https://git.kernel.org/stable/c/d8580e7aa189b0c6c5bb4d94b8352728a7c35bbd