CVE-2021-47006 ARM: 9064/1: hw_breakpoint: Do not directly check the event's overflow_handler hook

What is CVE-2021-47006?

CVE-2021-47006 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:

ARM: 9064/1: hw_breakpoint: Do not directly check the event's overflow_handler hook

The commit 1879445dfa7b ("perf/core: Set event's default ::overflow_handler()") set a default event->overflow_handler in perf_event_alloc(), and replace the check event->overflow_handler with is_default_overflow_handler(), but one is missing.

Currently, the bp->overflow_handler can not be NULL. As a result, enable_single_step() is always not invoked.

Comments from Zhen Lei:

https://patchwork.kernel.org/project/linux-arm-kernel/patch/[email protected]/

Which versions are affected by CVE-2021-47006?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2021-47006?

Apply the vendor's patch.

Is CVE-2021-47006 being exploited?

There is no known exploitation of CVE-2021-47006 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-2021-47006, GHSA-9rf2-394m-48f4, UBUNTU-CVE-2021-47006.