# CVE-2026-80551: s390/vfio_ccw: Ensure first IDAW remains constant

> A race condition in the s390 vfio_ccw driver allows attackers to manipulate IDAW addresses, potentially leading to memory corruption or privilege escalation.

- **Severity:** Critical 9.3 (`CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 26 Aug 2026
- **Updated:** 16 Oct 2026
- **Also known as:** AZL-97824, BELL-CVE-2026-80551, DEBIAN-CVE-2026-80551, GHSA-p29x-7599-2m4p, UBUNTU-CVE-2026-80551

## What is CVE-2026-80551?

CVE-2026-80551 is a critical vulnerability in Linux, published on 26 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:

s390/vfio_ccw: Ensure first IDAW remains constant

The first IDAW in a list does not need to be on a 2K/4K boundary
like all others, and so is read separately to accurately calculate
the size of the buffer needed to read the full IDAL.

Verify that the address found in the first IDAW is unchanged between
reads, to ensure a consistent set of IDAWs being worked with.

## Which versions are affected by CVE-2026-80551?


## How do I fix CVE-2026-80551?

Apply the vendor's patch.

## Is CVE-2026-80551 being exploited?

There is no known exploitation of CVE-2026-80551 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-80551 and fix it if it is affected.

What it is: CVE-2026-80551 is a critical vulnerability in Linux, published on 26 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-2026-80551 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-2026-80551/ (Markdown: https://insights.sbomify.com/CVE-2026-80551/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-80551
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-80551
- OSV: https://osv.dev/vulnerability/CVE-2026-80551

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-80551/
Summaries are generated and may contain mistakes; the official description above is the record.