# CVE-2023-4732: Race condition in Red Hat Enterprise Linux 6

> A local attacker can trigger a race condition in the Linux kernel memory management subsystem, causing a denial of service via an invalid opcode bug.

- **Severity:** Medium 4.7 (`CVSS:3.1/AV:L/AC:H/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:** 3 Oct 2023
- **Updated:** 7 Nov 2025
- **Also known as:** DEBIAN-CVE-2023-4732, GHSA-c9mw-vpxm-p7rq, UBUNTU-CVE-2023-4732

## What is CVE-2023-4732?

CVE-2023-4732 is a medium-severity vulnerability in Linux kernel, published on 3 Oct 2023. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A flaw was found in pfn_swap_entry_to_page in memory management subsystem in the Linux Kernel. In this flaw, an attacker with a local user privilege may cause a denial of service problem due to a BUG statement referencing pmd_t x.

Weakness: CWE-362 (Concurrent Execution using Shared Resource with Improper Synchronization), CWE-366 (Race Condition within a Thread)

## Which versions are affected by CVE-2023-4732?

It affects 10 products.


Products: Linux kernel, Redhat Codeready Linux Builder, Redhat Codeready Linux Builder for Arm64, Redhat Codeready Linux Builder for Power Little Endian, Redhat Enterprise Linux, Redhat Enterprise Linux for Arm 64, Redhat Enterprise Linux for Ibm Z Systems, Redhat Enterprise Linux for Power Little Endian, Redhat Enterprise Linux for Real Time, Redhat Enterprise Linux for Real Time for Nfv.

## How do I fix CVE-2023-4732?

Apply the vendor's patch.

## Is CVE-2023-4732 being exploited?

There is no known exploitation of CVE-2023-4732 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-2023-4732 and fix it if it is affected.

What it is: CVE-2023-4732 is a medium-severity vulnerability in Linux kernel, published on 3 Oct 2023. 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-2023-4732 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-2023-4732/ (Markdown: https://insights.sbomify.com/CVE-2023-4732/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-4732
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-4732
- OSV: https://osv.dev/vulnerability/CVE-2023-4732

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-4732/
Summaries are generated and may contain mistakes; the official description above is the record.