# CVE-2026-68342: ovpn: avoid putting unrelated P2P peer on socket release

> A use-after-free in the Linux kernel OVPN module allows local attackers to execute code or escalate privileges via socket release race conditions.

- **Severity:** Not scored
- **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:** 10 Aug 2026
- **Updated:** 17 Aug 2026
- **Also known as:** BELL-CVE-2026-68342, DEBIAN-CVE-2026-68342, GHSA-wh63-3892-rjx3, UBUNTU-CVE-2026-68342

## What is CVE-2026-68342?

CVE-2026-68342 is an 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:

ovpn: avoid putting unrelated P2P peer on socket release

ovpn_peer_release_p2p() is called when an OVPN UDP socket is being
destroyed. It checks the currently published P2P peer and releases it only
if that peer still uses the socket being destroyed.

A peer replacement can publish a new peer before the old UDP socket is
destroyed. When the old socket destruction path runs afterwards,
ovpn_peer_release_p2p() observes the new peer through ovpn->peer. Since the
new peer uses a different socket, the function takes the socket mismatch
branch.

That branch still calls ovpn_peer_put(peer). At this point, however, peer
is the currently published replacement peer, not the peer associated with
the socket being destroyed. Dropping its reference can free it while
ovpn->peer still points to it, leading to later use-after-free accesses
from the peer and socket cleanup paths.

KASAN reports this as a slab-use-after-free on the kmalloc-1k ovpn_peer
object. In the reproducer, the object is allocated from ovpn_peer_new() via
ovpn_nl_peer_new_doit(), and freed through ovpn_peer_release_rcu() from RCU
callback processing. Observed access sites include ovpn_peer_remove(),
ovpn_socket_release(), ovpn_nl_peer_del_notify(), and unlock_ovpn().

Fix this by returning from the socket mismatch branch without putting the
peer.

## Which versions are affected by CVE-2026-68342?


## How do I fix CVE-2026-68342?

Apply the vendor's patch.

## Is CVE-2026-68342 being exploited?

There is no known exploitation of CVE-2026-68342 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-68342 and fix it if it is affected.

What it is: CVE-2026-68342 is an 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-2026-68342 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-2026-68342/ (Markdown: https://insights.sbomify.com/CVE-2026-68342/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-68342
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-68342
- OSV: https://osv.dev/vulnerability/CVE-2026-68342

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-68342/
Summaries are generated and may contain mistakes; the official description above is the record.