# CVE-2026-80642: liveupdate: Reference count incoming FLB data

> A use-after-free vulnerability in the Linux kernel's liveupdate subsystem allows local attackers to potentially execute code or escalate privileges.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 28 Aug 2026
- **Updated:** 28 Aug 2026
- **Also known as:** DEBIAN-CVE-2026-80642, GHSA-pw7q-xpfh-rjvq, UBUNTU-CVE-2026-80642

## What is CVE-2026-80642?

CVE-2026-80642 is an use after free vulnerability in Linux, published on 28 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:

liveupdate: Reference count incoming FLB data

Increment the incoming FLB refcount in liveupdate_flb_get_incoming() so
that the FLB structure cannot be freed while the caller is actively using
it. Add an additional liveupdate_flb_put_incoming() function so the
caller can explicitly indicate when it is done using the FLB data.

During a Live Update, a subsystem might need to hold onto the incoming
File-Lifecycle-Bound (FLB) data for an extended period, such as during
device enumeration. Incrementing the reference count guarantees that the
data remains valid and accessible until the subsystem releases it,
preventing future use-after-free bugs.

## Which versions are affected by CVE-2026-80642?


## How do I fix CVE-2026-80642?

Apply the vendor's patch.

## Is CVE-2026-80642 being exploited?

There is no known exploitation of CVE-2026-80642 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-80642 and fix it if it is affected.

What it is: CVE-2026-80642 is an use after free vulnerability in Linux, published on 28 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-2026-80642 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-2026-80642/ (Markdown: https://insights.sbomify.com/CVE-2026-80642/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-80642
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-80642
- OSV: https://osv.dev/vulnerability/CVE-2026-80642

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-80642/
Summaries are generated and may contain mistakes; the official description above is the record.