# CVE-2026-23357: can: mcp251x: fix deadlock in error path of mcp251x_open

> A deadlock in the Linux kernel MCP251x CAN driver error path allows local attackers to cause a system hang.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/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:** 25 Mar 2026
- **Updated:** 15 Oct 2026
- **Also known as:** AZL-80685, BELL-CVE-2026-23357, DEBIAN-CVE-2026-23357, GHSA-f94p-fcww-cpfj, ROOT-OS-DEBIAN-11-CVE-2026-23357, ROOT-OS-DEBIAN-12-CVE-2026-23357, ROOT-OS-DEBIAN-13-CVE-2026-23357, ROOT-OS-UBUNTU-2204-CVE-2026-23357, ROOT-OS-UBUNTU-2404-CVE-2026-23357, UBUNTU-CVE-2026-23357

## What is CVE-2026-23357?

CVE-2026-23357 is a medium-severity vulnerability in Linux kernel, published on 25 Mar 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:

can: mcp251x: fix deadlock in error path of mcp251x_open

The mcp251x_open() function call free_irq() in its error path with the
mpc_lock mutex held. But if an interrupt already occurred the
interrupt handler will be waiting for the mpc_lock and free_irq() will
deadlock waiting for the handler to finish.

This issue is similar to the one fixed in commit 7dd9c26bd6cf ("can:
mcp251x: fix deadlock if an interrupt occurs during mcp251x_open") but
for the error path.

To solve this issue move the call to free_irq() after the lock is
released. Setting `priv->force_quit = 1` beforehand ensure that the IRQ
handler will exit right away once it acquired the lock.

Weakness: CWE-667 (Improper Locking)

## Which versions are affected by CVE-2026-23357?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-23357?

Apply the vendor's patch.

## Is CVE-2026-23357 being exploited?

There is no known exploitation of CVE-2026-23357 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-2026-23357 and fix it if it is affected.

What it is: CVE-2026-23357 is a medium-severity vulnerability in Linux kernel, published on 25 Mar 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-2026-23357 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-2026-23357/ (Markdown: https://insights.sbomify.com/CVE-2026-23357/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-23357
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-23357
- OSV: https://osv.dev/vulnerability/CVE-2026-23357

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-23357/
Summaries are generated and may contain mistakes; the official description above is the record.