# CVE-2026-98251: openvswitch: avoid reallocating confirmed conntrack labels

> A race condition in the Linux kernel's Open vSwitch module can cause a use-after-free when accessing conntrack labels, potentially leading to a system crash.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/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:** 6 Oct 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-106350, BELL-CVE-2026-98251, DEBIAN-CVE-2026-98251, GHSA-6vh8-2x3v-qcxv, UBUNTU-CVE-2026-98251

## What is CVE-2026-98251?

CVE-2026-98251 is a high-severity vulnerability in Linux, published on 6 Oct 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:

openvswitch: avoid reallocating confirmed conntrack labels

ovs_ct_get_conn_labels() adds the labels extension when a conntrack
entry does not have one.  Confirmed conntracks can be read locklessly,
so adding an extension may reallocate and free the extension block
while another CPU accesses it.

Only add the extension for unconfirmed conntracks.  A confirmed
conntrack without labels now fails the caller's label operation instead
of reallocating its extension storage.

## Which versions are affected by CVE-2026-98251?


## How do I fix CVE-2026-98251?

Apply the vendor's patch.

## Is CVE-2026-98251 being exploited?

There is no known exploitation of CVE-2026-98251 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-98251 and fix it if it is affected.

What it is: CVE-2026-98251 is a high-severity vulnerability in Linux, published on 6 Oct 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-2026-98251 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-2026-98251/ (Markdown: https://insights.sbomify.com/CVE-2026-98251/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-98251
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-98251
- OSV: https://osv.dev/vulnerability/CVE-2026-98251

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-98251/
Summaries are generated and may contain mistakes; the official description above is the record.