# CVE-2025-38008: mm/page_alloc: fix race condition in unaccepted memory handling

> A race condition in the Linux kernel's page allocator can trigger a warning and potential instability, requiring a patch to remove the flawed optimization.

- **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:** 18 Jun 2025
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2025-38008, DEBIAN-CVE-2025-38008, GHSA-qqq6-9fj8-x34c, ROOT-OS-UBUNTU-2404-CVE-2025-38008, UBUNTU-CVE-2025-38008

## What is CVE-2025-38008?

CVE-2025-38008 is a medium-severity vulnerability in Linux kernel, published on 18 Jun 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:

mm/page_alloc: fix race condition in unaccepted memory handling

The page allocator tracks the number of zones that have unaccepted memory
using static_branch_enc/dec() and uses that static branch in hot paths to
determine if it needs to deal with unaccepted memory.

Borislav and Thomas pointed out that the tracking is racy: operations on
static_branch are not serialized against adding/removing unaccepted pages
to/from the zone.

Sanity checks inside static_branch machinery detects it:

WARNING: CPU: 0 PID: 10 at kernel/jump_label.c:276 __static_key_slow_dec_cpuslocked+0x8e/0xa0

The comment around the WARN() explains the problem:

	/*
	 * Warn about the '-1' case though; since that means a
	 * decrement is concurrent with a first (0->1) increment. IOW
	 * people are trying to disable something that wasn't yet fully
	 * enabled. This suggests an ordering problem on the user side.
	 */

The effect of this static_branch optimization is only visible on
microbenchmark.

Instead of adding more complexity around it, remove it altogether.

Weakness: CWE-362 (Concurrent Execution using Shared Resource with Improper Synchronization)

## Which versions are affected by CVE-2025-38008?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2025-38008?

Apply the vendor's patch.

## Is CVE-2025-38008 being exploited?

There is no known exploitation of CVE-2025-38008 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-2025-38008 and fix it if it is affected.

What it is: CVE-2025-38008 is a medium-severity vulnerability in Linux kernel, published on 18 Jun 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-2025-38008 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-2025-38008/ (Markdown: https://insights.sbomify.com/CVE-2025-38008/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-38008
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-38008
- OSV: https://osv.dev/vulnerability/CVE-2025-38008

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-38008/
Summaries are generated and may contain mistakes; the official description above is the record.