# CVE-2026-89932: KVM: nVMX: Always flush vpid02 on first use

> A flaw in Linux KVM allows reading stale TLB entries from previous VM lifetimes, potentially disclosing sensitive memory data.

- **Severity:** High 8.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H`)
- **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:** Yes
- **Published:** 16 Sep 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-101610, BELL-CVE-2026-89932, DEBIAN-CVE-2026-89932, GHSA-8q77-gpg3-wgrc, UBUNTU-CVE-2026-89932

## What is CVE-2026-89932?

CVE-2026-89932 is a high-severity vulnerability in Linux, published on 16 Sep 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: nVMX: Always flush vpid02 on first use

Make sure vpid02 is always flushed on first use by setting last_vpid=0
when allocating vpid02.  nested_vmx_transition_tlb_flush() will always
detect a VPID change on first VM-Enter after VMXON, because VPID=0 in
vmcs12 is not allowed if L1 enables VPID.

This avoids using stale TLB entries from a previous lifetime of the
VPID, that might have been associated with a different vCPU (or a
completely different VM).

Note that last_vpid is already being initialized as 0 when the vCPU is
created, but it is not reset when vpid02 is freed on VMXOFF. Hence, the
problem can only occur if L1 does VMXOFF -> VMXON, runs an L2, and KVM
happens to reuse a VPID that has TLB entries on the physical CPU.

## Which versions are affected by CVE-2026-89932?


## How do I fix CVE-2026-89932?

Apply the vendor's patch.

## Is CVE-2026-89932 being exploited?

There is no known exploitation of CVE-2026-89932 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-89932 and fix it if it is affected.

What it is: CVE-2026-89932 is a high-severity vulnerability in Linux, published on 16 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-89932 in the wild and no public exploit code.

Affected product: Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-89932/ (Markdown: https://insights.sbomify.com/CVE-2026-89932/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-89932
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-89932
- OSV: https://osv.dev/vulnerability/CVE-2026-89932

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-89932/
Summaries are generated and may contain mistakes; the official description above is the record.