# CVE-2026-74607: KVM: SVM: Serialize accesses to the owner and mirror list with separate lock

> A race condition in KVM SVM allows list corruption and potential memory safety violations, enabling privilege escalation or code execution.

- **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:** 22 Aug 2026
- **Updated:** 16 Oct 2026
- **Also known as:** AZL-97085, BELL-CVE-2026-74607, DEBIAN-CVE-2026-74607, GHSA-v5cv-jrwx-xxrg, UBUNTU-CVE-2026-74607

## What is CVE-2026-74607?

CVE-2026-74607 is a high-severity vulnerability in Linux, published on 22 Aug 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: SVM: Serialize accesses to the owner and mirror list with separate lock

Interaction between KVM_CAP_VM_MOVE_ENC_CONTEXT_FROM and
KVM_CAP_VM_COPY_ENC_CONTEXT_FROM can cause two separate issues:

- in sev_migrate_from(), when the destination KVM is a mirror, the mirror
  entry is moved from the source's list to the owner's mirror_vms list,
  without holding the owner's lock unlike other writers of the owner's
  mirror list (sev_vm_copy_enc_context_from(), sev_vm_destroy()).
  A concurrent COPY or destroy can race with sev_migrate_from() and
  corrupt the list.

- In sev_vm_destroy(), the *owner* is still active and could receive
  concurrently a KVM_CAP_VM_MOVE_ENC_CONTEXT_FROM that causes
  sev->enc_context_owner to change.  In this case the incorrect VM
  receives kvm_put_kvm().

The second issue needs particular care because the owner could disappear
altogether (even though the race window is impossibly small) between
reading it and locking it.  There is thus no way to perform the checks
under the owner lock without putting struct kvm under SLAB_TYPESAFE_BY_RCU
(which would allow kvm_get_kvm_safe() under RCU critical section).

It is much simpler to just use a global lock, since the critical
sections are so small and the new lock is always a leaf lock.

## Which versions are affected by CVE-2026-74607?


## How do I fix CVE-2026-74607?

Apply the vendor's patch.

## Is CVE-2026-74607 being exploited?

There is no known exploitation of CVE-2026-74607 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-74607 and fix it if it is affected.

What it is: CVE-2026-74607 is a high-severity vulnerability in Linux, published on 22 Aug 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-2026-74607 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-2026-74607/ (Markdown: https://insights.sbomify.com/CVE-2026-74607/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-74607
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-74607
- OSV: https://osv.dev/vulnerability/CVE-2026-74607

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-74607/
Summaries are generated and may contain mistakes; the official description above is the record.