# CVE-2026-72283: KVM: x86: Nullify irqfd->producer if updating IRTE for bypass fails

> A use-after-free in KVM x86 allows attackers to execute arbitrary code or escalate privileges via dangling pointers in irqfd handling.

- **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:** 15 Aug 2026
- **Updated:** 17 Aug 2026
- **Also known as:** BELL-CVE-2026-72283, DEBIAN-CVE-2026-72283, GHSA-ww73-cj9w-h762, UBUNTU-CVE-2026-72283

## What is CVE-2026-72283?

CVE-2026-72283 is a high-severity use after free vulnerability in Linux, published on 15 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: x86: Nullify irqfd->producer if updating IRTE for bypass fails

Nullify irqfd->producer if updating the IRTE for bypass fails, as leaving a
dangling pointer will result in a use-after-free if the irqfd is reachable
through KVM's routing, but the producer is freed separately.  E.g. for VFIO
PCI, the producer is embedded in struct "vfio_pci_irq_ctx" and freed when
the vector is disabled, which can happen independent of routing updates.

[sean: drop PPC change, massage changelog]

## Which versions are affected by CVE-2026-72283?


## How do I fix CVE-2026-72283?

Apply the vendor's patch.

## Is CVE-2026-72283 being exploited?

There is no known exploitation of CVE-2026-72283 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-72283 and fix it if it is affected.

What it is: CVE-2026-72283 is a high-severity use after free vulnerability in Linux, published on 15 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-2026-72283 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-2026-72283/ (Markdown: https://insights.sbomify.com/CVE-2026-72283/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-72283
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-72283
- OSV: https://osv.dev/vulnerability/CVE-2026-72283

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-72283/
Summaries are generated and may contain mistakes; the official description above is the record.