CVE-2021-46994 can: mcp251x: fix resume from sleep before interface was brought up

What is CVE-2021-46994?

CVE-2021-46994 is a medium-severity vulnerability in Linux kernel, published on 28 Feb 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:

can: mcp251x: fix resume from sleep before interface was brought up

Since 8ce8c0abcba3 the driver queues work via priv->restart_work when resuming after suspend, even when the interface was not previously enabled. This causes a null dereference error as the workqueue is only allocated and initialized in mcp251x_open().

To fix this we move the workqueue init to mcp251x_can_probe() as there is no reason to do it later and repeat it whenever mcp251x_open() is called.

[mkl: fix error handling in mcp251x_stop()]

Weakness: CWE-476

Which versions are affected by CVE-2021-46994?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2021-46994?

Apply the vendor's patch.

Is CVE-2021-46994 being exploited?

There is no known exploitation of CVE-2021-46994 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 DEBIAN-CVE-2021-46994, GHSA-9h3w-jq64-m799, UBUNTU-CVE-2021-46994.