CVE-2021-28971 Denial of service in n/a

What is CVE-2021-28971?

CVE-2021-28971 is a medium-severity denial of service vulnerability in Debian Debian Linux, published on 22 Mar 2021. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

In intel_pmu_drain_pebs_nhm in arch/x86/events/intel/ds.c in the Linux kernel through 5.11.8 on some Haswell CPUs, userspace applications (such as perf-fuzzer) can cause a system crash because the PEBS status in a PEBS record is mishandled, aka CID-d88d05a9e0b6.

Weakness: CWE-755

Which versions are affected by CVE-2021-28971?

It affects 7 products.

Products include Debian Debian Linux, Fedoraproject Fedora, Linux kernel, Netapp Aff 500f Firmware, Netapp Aff A250 Firmware, Netapp Cloud Backup and 1 more.

How do I fix CVE-2021-28971?

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-2021-28971 being exploited?

There is no known exploitation of CVE-2021-28971 in the wild and no public exploit code.

Other vulnerabilities in Debian Debian Linux

• CVE-2015-3306 ProFTPD Improper Access Control Exploited Critical 10.0
• CVE-2025-49113 RoundCube Webmail Deserialization of Untrusted Data Exploited Critical 9.9
• CVE-2026-24061 GNU InetUtils Argument Injection Exploited Critical 9.8
• CVE-2025-39682 Linux Kernel Improper Check for Unusual or Exceptional Conditions Exploited Critical 9.8
• CVE-2024-9680 Mozilla Firefox Use-After-Free Exploited Critical 9.8

All Debian Debian Linux vulnerabilities

Sources

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

Also known as AZL-6542, DEBIAN-CVE-2021-28971, GHSA-xjrj-6839-jg74, UBUNTU-CVE-2021-28971.