# CVE-2025-37989: net: phy: leds: fix memory leak

> A memory leak in the Linux kernel PHY LED trigger code can cause out-of-memory conditions during network restarts, leading to denial of service.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/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:** 20 May 2025
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2025-37989, DEBIAN-CVE-2025-37989, GHSA-ff73-mwmp-6jw5, ROOT-OS-DEBIAN-11-CVE-2025-37989, ROOT-OS-UBUNTU-2204-CVE-2025-37989, ROOT-OS-UBUNTU-2404-CVE-2025-37989, UBUNTU-CVE-2025-37989

## What is CVE-2025-37989?

CVE-2025-37989 is a medium-severity denial of service vulnerability in Debian Debian Linux, published on 20 May 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:

net: phy: leds: fix memory leak

A network restart test on a router led to an out-of-memory condition,
which was traced to a memory leak in the PHY LED trigger code.

The root cause is misuse of the devm API. The registration function
(phy_led_triggers_register) is called from phy_attach_direct, not
phy_probe, and the unregister function (phy_led_triggers_unregister)
is called from phy_detach, not phy_remove. This means the register and
unregister functions can be called multiple times for the same PHY
device, but devm-allocated memory is not freed until the driver is
unbound.

This also prevents kmemleak from detecting the leak, as the devm API
internally stores the allocated pointer.

Fix this by replacing devm_kzalloc/devm_kcalloc with standard
kzalloc/kcalloc, and add the corresponding kfree calls in the unregister
path.

Weakness: CWE-401 (Missing Release of Memory after Effective Lifetime)

## Which versions are affected by CVE-2025-37989?

It affects 2 products.


Products: Debian Debian Linux, Linux kernel.

## How do I fix CVE-2025-37989?

Apply the vendor's patch.

## Is CVE-2025-37989 being exploited?

There is no known exploitation of CVE-2025-37989 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-2025-37989 and fix it if it is affected.

What it is: CVE-2025-37989 is a medium-severity denial of service vulnerability in Debian Debian Linux, published on 20 May 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-2025-37989 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-2025-37989/ (Markdown: https://insights.sbomify.com/CVE-2025-37989/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-37989
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-37989
- OSV: https://osv.dev/vulnerability/CVE-2025-37989

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-37989/
Summaries are generated and may contain mistakes; the official description above is the record.