CVE-2021-47016 m68k: mvme147,mvme16x: Don't wipe PCC timer config bits

What is CVE-2021-47016?

CVE-2021-47016 is a medium-severity denial of service vulnerability in Linux kernel, published on 29 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:

m68k: mvme147,mvme16x: Don't wipe PCC timer config bits

Don't clear the timer 1 configuration bits when clearing the interrupt flag and counter overflow. As Michael reported, "This results in no timer interrupts being delivered after the first. Initialization then hangs in calibrate_delay as the jiffies counter is not updated."

On mvme16x, enable the timer after requesting the irq, consistent with mvme147.

Which versions are affected by CVE-2021-47016?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2021-47016?

Apply the vendor's patch.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2021-47016 being exploited?

There is no known exploitation of CVE-2021-47016 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-2021-47016, GHSA-8gv8-jqm3-r824, UBUNTU-CVE-2021-47016.