CVE-2026-31736 net: ethernet: mtk_ppe: avoid NULL deref when gmac0 is disabled

What is CVE-2026-31736?

CVE-2026-31736 is a medium-severity vulnerability in Linux kernel, published on 1 May 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: ethernet: mtk_ppe: avoid NULL deref when gmac0 is disabled

If the gmac0 is disabled, the precheck for a valid ingress device will cause a NULL pointer deref and crash the system. This happens because eth->netdev[0] will be NULL but the code will directly try to access netdev_ops.

Instead of just checking for the first net_device, it must be checked if any of the mtk_eth net_devices is matching the netdev_ops of the ingress device.

Weakness: CWE-476

Which versions are affected by CVE-2026-31736?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2026-31736?

Apply the vendor's patch.

Is CVE-2026-31736 being exploited?

There is no known exploitation of CVE-2026-31736 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BELL-CVE-2026-31736, DEBIAN-CVE-2026-31736, GHSA-pp62-pwj6-ppp4, UBUNTU-CVE-2026-31736.