# CVE-2025-38538: dmaengine: nbpfaxi: Fix memory corruption in probe()

> A memory corruption vulnerability in the Linux kernel's nbpfaxi DMA driver allows attackers to potentially execute arbitrary code or escalate privileges.

- **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:** 16 Aug 2025
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2025-38538, DEBIAN-CVE-2025-38538, GHSA-646r-2h84-3p3v, ROOT-OS-DEBIAN-11-CVE-2025-38538, ROOT-OS-DEBIAN-12-CVE-2025-38538, ROOT-OS-DEBIAN-13-CVE-2025-38538, ROOT-OS-UBUNTU-2204-CVE-2025-38538, ROOT-OS-UBUNTU-2404-CVE-2025-38538, UBUNTU-CVE-2025-38538

## What is CVE-2025-38538?

CVE-2025-38538 is a high-severity memory corruption vulnerability in Debian Debian Linux, published on 16 Aug 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:

dmaengine: nbpfaxi: Fix memory corruption in probe()

The nbpf->chan[] array is allocated earlier in the nbpf_probe() function
and it has "num_channels" elements.  These three loops iterate one
element farther than they should and corrupt memory.

The changes to the second loop are more involved.  In this case, we're
copying data from the irqbuf[] array into the nbpf->chan[] array.  If
the data in irqbuf[i] is the error IRQ then we skip it, so the iterators
are not in sync.  I added a check to ensure that we don't go beyond the
end of the irqbuf[] array.  I'm pretty sure this can't happen, but it
seemed harmless to add a check.

On the other hand, after the loop has ended there is a check to ensure
that the "chan" iterator is where we expect it to be.  In the original
code we went one element beyond the end of the array so the iterator
wasn't in the correct place and it would always return -EINVAL.  However,
now it will always be in the correct place.  I deleted the check since
we know the result.

Weakness: CWE-787 (Out-of-bounds Write)

## Which versions are affected by CVE-2025-38538?

It affects 2 products.


Products: Debian Debian Linux, Linux kernel.

## How do I fix CVE-2025-38538?

Apply the vendor's patch.

## Is CVE-2025-38538 being exploited?

There is no known exploitation of CVE-2025-38538 in the wild and no public exploit code.

## Other vulnerabilities in Debian Debian Linux

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- [CVE-2026-24061](https://insights.sbomify.com/CVE-2026-24061/): GNU InetUtils Argument Injection (critical 9.8, exploited in the wild)
- [CVE-2025-39682](https://insights.sbomify.com/CVE-2025-39682/): Linux Kernel Improper Check for Unusual or Exceptional Conditions (critical 9.8, exploited in the wild)
- [CVE-2024-9680](https://insights.sbomify.com/CVE-2024-9680/): Mozilla Firefox Use-After-Free (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-38538 and fix it if it is affected.

What it is: CVE-2025-38538 is a high-severity memory corruption vulnerability in Debian Debian Linux, published on 16 Aug 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-2025-38538 in the wild and no public exploit code.

Affected product: Debian Debian Linux. 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-2025-38538/ (Markdown: https://insights.sbomify.com/CVE-2025-38538/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-38538
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-38538
- OSV: https://osv.dev/vulnerability/CVE-2025-38538

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-38538/
Summaries are generated and may contain mistakes; the official description above is the record.