CVE-2026-46059 KVM: nSVM: Always use NextRIP as vmcb02's NextRIP after first L2 VMRUN
A logic error in KVM nested virtualization handling of NextRIP can cause incorrect state restoration, potentially leading to guest instability or denial of service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-46059?
CVE-2026-46059 is a medium-severity vulnerability in Linux kernel, published on 27 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
KVM: nSVM: Always use NextRIP as vmcb02's NextRIP after first L2 VMRUN
For guests with NRIPS disabled, L1 does not provide NextRIP when running an L2 with an injected soft interrupt, instead it advances the current RIP before running it. KVM uses the current RIP as the NextRIP in vmcb02 to emulate a CPU without NRIPS.
However, after L2 runs the first time, NextRIP will be updated by the CPU and/or KVM, and the current RIP is no longer the correct value to use in vmcb02. Hence, after save/restore, use the current RIP if and only if a nested run is pending, otherwise use NextRIP. Give soft_int_next_rip the same treatment, as it's the same logic, just for a narrower use case.
[sean: give soft_int_next_rip the same treatment]
Which versions are affected by CVE-2026-46059?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-46059?
Apply the vendor's patch.
Is CVE-2026-46059 being exploited?
There is no known exploitation of CVE-2026-46059 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-88685, BELL-CVE-2026-46059, DEBIAN-CVE-2026-46059, GHSA-fhch-vffp-hj8x, ROOT-OS-DEBIAN-11-CVE-2026-46059, ROOT-OS-DEBIAN-12-CVE-2026-46059 and 4 more.