# CVE-2026-68140: net/iucv: fix use-after-free of a severed iucv_path

> A use-after-free in the Linux kernel's IUCV network module allows attackers to cause denial of service or potentially execute code via crafted network messages.

- **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-2026-68140, DEBIAN-CVE-2026-68140, GHSA-8p4m-4f3f-9xqp, UBUNTU-CVE-2026-68140

## What is CVE-2026-68140?

CVE-2026-68140 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: fix use-after-free of a severed iucv_path

af_iucv queues not-yet-received message notifications on iucv->message_q,
each holding a raw pointer to the connection's iucv_path.  When the peer
severs the connection, iucv_sever_path() frees that path with
iucv_path_free() but leaves the notifications queued.  A later recvmsg()
drains message_q via iucv_process_message_q() and hands the stale path to
message_receive() -- a use-after-free of the freed iucv_path.

Drop the queued notifications when the path is severed; once the path is
gone they can no longer be received.  This also frees the notifications
leaked when a socket is closed with messages still queued.

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2026-68140?


## How do I fix CVE-2026-68140?

Apply the vendor's patch.

## Is CVE-2026-68140 being exploited?

There is no known exploitation of CVE-2026-68140 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-68140 and fix it if it is affected.

What it is: CVE-2026-68140 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-2026-68140 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-2026-68140/ (Markdown: https://insights.sbomify.com/CVE-2026-68140/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-68140
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-68140
- OSV: https://osv.dev/vulnerability/CVE-2026-68140

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-68140/
Summaries are generated and may contain mistakes; the official description above is the record.