# CVE-2022-50421: rpmsg: char: Avoid double destroy of default endpoint

> A use-after-free vulnerability in the Linux kernel rpmsg driver allows attackers to cause a denial of service or potentially execute code via double destruction of an endpoint.

- **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:** 1 Oct 2025
- **Updated:** 5 Aug 2026
- **Also known as:** DEBIAN-CVE-2022-50421, GHSA-7gv2-7hhr-4fm9, UBUNTU-CVE-2022-50421

## What is CVE-2022-50421?

CVE-2022-50421 is a high-severity use after free vulnerability in Linux kernel, published on 1 Oct 2025. 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:

rpmsg: char: Avoid double destroy of default endpoint

The rpmsg_dev_remove() in rpmsg_core is the place for releasing
this default endpoint.

So need to avoid destroying the default endpoint in
rpmsg_chrdev_eptdev_destroy(), this should be the same as
rpmsg_eptdev_release(). Otherwise there will be double destroy
issue that ept->refcount report warning:

refcount_t: underflow; use-after-free.

Call trace:
 refcount_warn_saturate+0xf8/0x150
 virtio_rpmsg_destroy_ept+0xd4/0xec
 rpmsg_dev_remove+0x60/0x70

The issue can be reproduced by stopping remoteproc before
closing the /dev/rpmsgX.

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2022-50421?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2022-50421?

Apply the vendor's patch.

## Is CVE-2022-50421 being exploited?

There is no known exploitation of CVE-2022-50421 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2022-50421 and fix it if it is affected.

What it is: CVE-2022-50421 is a high-severity use after free vulnerability in Linux kernel, published on 1 Oct 2025. 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-2022-50421 in the wild and no public exploit code.

Affected product: Linux kernel. 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-2022-50421/ (Markdown: https://insights.sbomify.com/CVE-2022-50421/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-50421
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-50421
- OSV: https://osv.dev/vulnerability/CVE-2022-50421

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-50421/
Summaries are generated and may contain mistakes; the official description above is the record.