# CVE-2025-38331: net: ethernet: cortina: Use TOE/TSO on all TCP

> A flaw in the Cortina Ethernet driver causes system lockups and crashes when handling non-segmented TCP frames, leading to denial of service.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 10 Jul 2025
- **Updated:** 5 Aug 2026
- **Also known as:** AZL-64901, AZL-72835, BELL-CVE-2025-38331, DEBIAN-CVE-2025-38331, GHSA-78v2-9wxw-73qf, ROOT-OS-DEBIAN-11-CVE-2025-38331, ROOT-OS-DEBIAN-12-CVE-2025-38331, ROOT-OS-UBUNTU-2204-CVE-2025-38331, ROOT-OS-UBUNTU-2404-CVE-2025-38331, UBUNTU-CVE-2025-38331

## What is CVE-2025-38331?

CVE-2025-38331 is a high-severity denial of service vulnerability in Debian Debian Linux, published on 10 Jul 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

net: ethernet: cortina: Use TOE/TSO on all TCP

It is desireable to push the hardware accelerator to also
process non-segmented TCP frames: we pass the skb->len
to the "TOE/TSO" offloader and it will handle them.

Without this quirk the driver becomes unstable and lock
up and and crash.

I do not know exactly why, but it is probably due to the
TOE (TCP offload engine) feature that is coupled with the
segmentation feature - it is not possible to turn one
part off and not the other, either both TOE and TSO are
active, or neither of them.

Not having the TOE part active seems detrimental, as if
that hardware feature is not really supposed to be turned
off.

The datasheet says:

  "Based on packet parsing and TCP connection/NAT table
   lookup results, the NetEngine puts the packets
   belonging to the same TCP connection to the same queue
   for the software to process. The NetEngine puts
   incoming packets to the buffer or series of buffers
   for a jumbo packet. With this hardware acceleration,
   IP/TCP header parsing, checksum validation and
   connection lookup are offloaded from the software
   processing."

After numerous tests with the hardware locking up after
something between minutes and hours depending on load
using iperf3 I have concluded this is necessary to stabilize
the hardware.

## Which versions are affected by CVE-2025-38331?

It affects 2 products.


Products: Debian Debian Linux, Linux kernel.

## How do I fix CVE-2025-38331?

Apply the vendor's patch.

## Is CVE-2025-38331 being exploited?

There is no known exploitation of CVE-2025-38331 in the wild and no public exploit code.

## Other vulnerabilities in Debian Debian Linux

- [CVE-2015-3306](https://insights.sbomify.com/CVE-2015-3306/): ProFTPD Improper Access Control (critical 10.0, exploited in the wild)
- [CVE-2025-49113](https://insights.sbomify.com/CVE-2025-49113/): RoundCube Webmail Deserialization of Untrusted Data (critical 9.9, exploited in the wild)
- [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-2025-38331 and fix it if it is affected.

What it is: CVE-2025-38331 is a high-severity denial of service vulnerability in Debian Debian Linux, published on 10 Jul 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2025-38331 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-2025-38331/ (Markdown: https://insights.sbomify.com/CVE-2025-38331/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-38331
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-38331
- OSV: https://osv.dev/vulnerability/CVE-2025-38331

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-38331/
Summaries are generated and may contain mistakes; the official description above is the record.