# CVE-2026-68397: net/iucv: take a reference on the socket found in afiucv_hs_rcv()

> A use-after-free vulnerability in the Linux kernel's IUCV network module allows attackers to cause denial of service or execute arbitrary code via race conditions.

- **Severity:** High 8.8 (`CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/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:** 10 Aug 2026
- **Updated:** 19 Oct 2026
- **Also known as:** BELL-CVE-2026-68397, DEBIAN-CVE-2026-68397, GHSA-7m4h-5x7q-hf25, UBUNTU-CVE-2026-68397

## What is CVE-2026-68397?

CVE-2026-68397 is a high-severity use after free vulnerability in Linux, published on 10 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:

net/iucv: take a reference on the socket found in afiucv_hs_rcv()

afiucv_hs_rcv() looks up the destination socket under iucv_sk_list.lock,
drops the lock, and then passes the socket to the afiucv_hs_callback_*()
handlers without holding a reference. AF_IUCV sockets are not
RCU-protected and are freed synchronously by iucv_sock_kill() ->
sock_put(), so a concurrent close can free the socket in the window
between read_unlock() and the handler, which then dereferences freed
memory (for example sk->sk_data_ready() in afiucv_hs_callback_syn()).

Take a reference with sock_hold() while the socket is still on the list
and release it with sock_put() once the handler has run.

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2026-68397?


## How do I fix CVE-2026-68397?

Apply the vendor's patch.

## Is CVE-2026-68397 being exploited?

There is no known exploitation of CVE-2026-68397 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-68397 and fix it if it is affected.

What it is: CVE-2026-68397 is a high-severity use after free vulnerability in Linux, published on 10 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-2026-68397 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-2026-68397/ (Markdown: https://insights.sbomify.com/CVE-2026-68397/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-68397
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-68397
- OSV: https://osv.dev/vulnerability/CVE-2026-68397

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-68397/
Summaries are generated and may contain mistakes; the official description above is the record.