CVE-2021-47560 mlxsw: spectrum: Protect driver from buggy firmware

What is CVE-2021-47560?

CVE-2021-47560 is a medium-severity vulnerability in Linux kernel, published on 24 May 2024. 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:

mlxsw: spectrum: Protect driver from buggy firmware

When processing port up/down events generated by the device's firmware, the driver protects itself from events reported for non-existent local ports, but not the CPU port (local port 0), which exists, but lacks a netdev.

This can result in a NULL pointer dereference when calling netif_carrier_{on,off}().

Fix this by bailing early when processing an event reported for the CPU port. Problem was only observed when running on top of a buggy emulator.

Weakness: CWE-476

Which versions are affected by CVE-2021-47560?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2021-47560?

Apply the vendor's patch.

Is CVE-2021-47560 being exploited?

There is no known exploitation of CVE-2021-47560 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
• How this page is made

Also known as DEBIAN-CVE-2021-47560, UBUNTU-CVE-2021-47560.