# CVE-2026-72032: net/mlx5: HWS, fix matcher leak on resize target setup failure

> A memory leak in the Linux kernel mlx5 HWS driver allows local attackers to cause denial of service by triggering resize failures.

- **Severity:** Not scored
- **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:** 15 Aug 2026
- **Updated:** 17 Aug 2026
- **Also known as:** BELL-CVE-2026-72032, DEBIAN-CVE-2026-72032, GHSA-j7xx-3c7m-pgh9, UBUNTU-CVE-2026-72032

## What is CVE-2026-72032?

CVE-2026-72032 is a memory corruption vulnerability in Linux, published on 15 Aug 2026. 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:

net/mlx5: HWS, fix matcher leak on resize target setup failure

hws_bwc_matcher_move() allocates a replacement matcher before setting it
as the resize target. If mlx5hws_matcher_resize_set_target() fails, the
replacement matcher is not attached anywhere and is leaked.

Fix the leak by destroying the replacement matcher before returning from
the resize-target failure path.

The bug was first flagged by an experimental analysis tool we are
developing for kernel memory-management bugs while analyzing
v6.13-rc1. The tool is still under development and is not yet publicly
available. Manual inspection confirms that the bug is still
present in v7.1.1.

An x86_64 allyesconfig build showed no new warnings. As we do not have a
mlx5 HWS-capable device to test with, no runtime testing was able to be
performed.

## Which versions are affected by CVE-2026-72032?


## How do I fix CVE-2026-72032?

Apply the vendor's patch.

## Is CVE-2026-72032 being exploited?

There is no known exploitation of CVE-2026-72032 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-72032 and fix it if it is affected.

What it is: CVE-2026-72032 is a memory corruption vulnerability in Linux, published on 15 Aug 2026. 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-2026-72032 in the wild and no public exploit code.

Affected product: 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-2026-72032/ (Markdown: https://insights.sbomify.com/CVE-2026-72032/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-72032
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-72032
- OSV: https://osv.dev/vulnerability/CVE-2026-72032

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-72032/
Summaries are generated and may contain mistakes; the official description above is the record.