CVE-2025-40239

In the Linux kernel, the following vulnerability has been resolved: net: phy: micrel: always set shared->phydev for LAN8814 Currently, during the LAN8814 PTP probe shared->phydev is only set if PTP clock gets actually set, otherwise the function will return before setting it. This is an issue as shared->phydev is unconditionally being used when IRQ is being handled, especially in lan8814_gpio_process_cap and since it was not set it will cause a NULL pointer exception and crash the kernel. So, simply always set shared->phydev to avoid the NULL pointer exception.

Package Linux Kernel
Published 2025-12-04
Last modified 2026-04-15
Patch available
Yes

Affected versions

Linux kernel versions 6.10 and later are affected. Fixed in 6.12.56, 6.17.6, 6.18 and their respective stable series.

Affected from
≥ 6.10
Fixed in
✓ 6.12.56 6.12.x ✓ 6.17.6 6.17.x ✓ 6.18

References

The following references provide additional information about CVE-2025-40239 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.

Frequently asked questions

  • What is CVE-2025-40239?

    CVE-2025-40239 is a unscored severity Linux kernel vulnerability . It affects Linux kernel versions from 6.10 onward and has been patched in 6.12.56, 6.17.6 and 6.18. CVE-2025-40239 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

  • Is there a patch available for CVE-2025-40239?

    Yes — CVE-2025-40239 has been patched. Fixed versions include 6.12.56, 6.17.6 and 6.18. If you are running Linux kernel 6.10 or later up to the fix versions, apply the relevant patch for your kernel branch.

  • Is CVE-2025-40239 actively exploited?

    No — CVE-2025-40239 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.