# CVE-2026-98320: netfilter: flowtable: hold reference on ct until flow is released

> A use-after-free in the Linux kernel netfilter flowtable allows attackers to execute arbitrary code or escalate privileges.

- **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-106083, BELL-CVE-2026-98320, DEBIAN-CVE-2026-98320, GHSA-7rm7-mf5x-673x, UBUNTU-CVE-2026-98320

## What is CVE-2026-98320?

CVE-2026-98320 is a high-severity use after free 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:

netfilter: flowtable: hold reference on ct until flow is released

nf_ct_put() releases the ct->ext area inmediately, the rcu typesafe
semantics also allow to refer to the wrong conntrack from the flowtable
datapath. Hold reference on ct until flow is released after rcu grace
period.

Add rcu_barrier() on module exit path, to ensure pending flow entries
are release before module goes away.

## Which versions are affected by CVE-2026-98320?


## How do I fix CVE-2026-98320?

Apply the vendor's patch.

## Is CVE-2026-98320 being exploited?

There is no known exploitation of CVE-2026-98320 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-98320 and fix it if it is affected.

What it is: CVE-2026-98320 is a high-severity use after free 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-2026-98320 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-2026-98320/ (Markdown: https://insights.sbomify.com/CVE-2026-98320/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-98320
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-98320
- OSV: https://osv.dev/vulnerability/CVE-2026-98320

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-98320/
Summaries are generated and may contain mistakes; the official description above is the record.