CVE-2026-72288: KVM: arm64: vgic: Handle race between interrupt affinity change and LPI disabling
In the Linux kernel, the following vulnerability has been resolved:
KVM: arm64: vgic: Handle race between interrupt affinity change and LPI disabling
Hyunwoo Kim reports some really bad races should the following situation occur:
- LPI-I is pending in vcpu-B's AP list - vcpu-A writes to vcpu-B's RD to disable its LPIs - vcpu-C moves I from B to C
If the last two race nicely enough, vgicpruneaplist() can drop the irq and AP list locks, reacquire them, and in the interval the irq has been freed. UAF follows.
The fix is two-fold:
- Before dropping the irq and aplist locks, take a reference on the irq
- Do not try to handle migration of the pending bit: there is no expectation that this state is retained, as per the architecture
With that, we're sure that the interrupt is still around, and we safely remove it from the AP list as it has no target at this stage (unless another interrupt fires, but that's another story).
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2026-72288?
CVE-2026-72288 has a risk score of 51, indicating a notable severity that could impact system stability.
How do I fix CVE-2026-72288?
To fix CVE-2026-72288, ensure that your system is updated with the latest patches from the Linux kernel that address this vulnerability.
What systems are affected by CVE-2026-72288?
CVE-2026-72288 affects Linux systems using the KVM virtualization with arm64 architecture.
What are the potential impacts of CVE-2026-72288?
The potential impacts of CVE-2026-72288 include system instability due to race conditions involving interrupt affinity changes.
Who reported CVE-2026-72288?
CVE-2026-72288 was reported by Hyunwoo Kim, highlighting serious race conditions within the KVM component.