# CVE-2024-42253: gpio: pca953x: fix pca953x_irq_bus_sync_unlock race

> A race condition in the Linux kernel PCA953x GPIO driver can cause incorrect register writes, potentially leading to system instability or denial of service.

- **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:** 8 Aug 2024
- **Updated:** 5 Aug 2026
- **Also known as:** AZL-48811, BELL-CVE-2024-42253, DEBIAN-CVE-2024-42253, GHSA-gr3w-p7mm-8pcq, ROOT-OS-DEBIAN-11-CVE-2024-42253, ROOT-OS-UBUNTU-2204-CVE-2024-42253, UBUNTU-CVE-2024-42253

## What is CVE-2024-42253?

CVE-2024-42253 is a high-severity vulnerability in Linux kernel, published on 8 Aug 2024. 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:

gpio: pca953x: fix pca953x_irq_bus_sync_unlock race

Ensure that `i2c_lock' is held when setting interrupt latch and mask in
pca953x_irq_bus_sync_unlock() in order to avoid races.

The other (non-probe) call site pca953x_gpio_set_multiple() ensures the
lock is held before calling pca953x_write_regs().

The problem occurred when a request raced against irq_bus_sync_unlock()
approximately once per thousand reboots on an i.MX8MP based system.

 * Normal case

   0-0022: write register AI|3a {03,02,00,00,01} Input latch P0
   0-0022: write register AI|49 {fc,fd,ff,ff,fe} Interrupt mask P0
   0-0022: write register AI|08 {ff,00,00,00,00} Output P3
   0-0022: write register AI|12 {fc,00,00,00,00} Config P3

 * Race case

   0-0022: write register AI|08 {ff,00,00,00,00} Output P3
   0-0022: write register AI|08 {03,02,00,00,01} *** Wrong register ***
   0-0022: write register AI|12 {fc,00,00,00,00} Config P3
   0-0022: write register AI|49 {fc,fd,ff,ff,fe} Interrupt mask P0

Weakness: CWE-667 (Improper Locking)

## Which versions are affected by CVE-2024-42253?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-42253?

Apply the vendor's patch.

## Is CVE-2024-42253 being exploited?

There is no known exploitation of CVE-2024-42253 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-2024-42253 and fix it if it is affected.

What it is: CVE-2024-42253 is a high-severity vulnerability in Linux kernel, published on 8 Aug 2024. 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-2024-42253 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-2024-42253/ (Markdown: https://insights.sbomify.com/CVE-2024-42253/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-42253
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-42253
- OSV: https://osv.dev/vulnerability/CVE-2024-42253

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-42253/
Summaries are generated and may contain mistakes; the official description above is the record.