# CVE-2025-38537: net: phy: Don't register LEDs for genphy

> A deadlock in the Linux kernel network PHY subsystem can cause a denial of service when generic PHYs with LED nodes are detached.

- **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:** 16 Aug 2025
- **Updated:** 11 May 2026
- **Also known as:** AZL-66408, BELL-CVE-2025-38537, DEBIAN-CVE-2025-38537, GHSA-wcfp-94c7-jmv4, ROOT-OS-DEBIAN-13-CVE-2025-38537, ROOT-OS-UBUNTU-2404-CVE-2025-38537, UBUNTU-CVE-2025-38537

## What is CVE-2025-38537?

CVE-2025-38537 is a medium-severity denial of service vulnerability in Linux kernel, 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:

net: phy: Don't register LEDs for genphy

If a PHY has no driver, the genphy driver is probed/removed directly in
phy_attach/detach. If the PHY's ofnode has an "leds" subnode, then the
LEDs will be (un)registered when probing/removing the genphy driver.
This could occur if the leds are for a non-generic driver that isn't
loaded for whatever reason. Synchronously removing the PHY device in
phy_detach leads to the following deadlock:

rtnl_lock()
ndo_close()
    ...
    phy_detach()
        phy_remove()
            phy_leds_unregister()
                led_classdev_unregister()
                    led_trigger_set()
                        netdev_trigger_deactivate()
                            unregister_netdevice_notifier()
                                rtnl_lock()

There is a corresponding deadlock on the open/register side of things
(and that one is reported by lockdep), but it requires a race while this
one is deterministic.

Generic PHYs do not support LEDs anyway, so don't bother registering
them.

## Which versions are affected by CVE-2025-38537?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2025-38537?

Apply the vendor's patch.

## Is CVE-2025-38537 being exploited?

There is no known exploitation of CVE-2025-38537 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-2025-38537 and fix it if it is affected.

What it is: CVE-2025-38537 is a medium-severity denial of service vulnerability in Linux kernel, 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-2025-38537 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-2025-38537/ (Markdown: https://insights.sbomify.com/CVE-2025-38537/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-38537
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-38537
- OSV: https://osv.dev/vulnerability/CVE-2025-38537

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-38537/
Summaries are generated and may contain mistakes; the official description above is the record.