#VU64830 Resource exhaustion in Linux kernel - CVE-2021-28971

Vulnerability identifier: #VU64830

Vulnerability risk: Low

CVSSv4.0: 4.3 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-28971

CWE-ID: CWE-400

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
Linux kernel
Operating systems & Components / Operating system

Vendor: Linux Foundation

Description

The vulnerability allows a local user to perform a denial of service (DoS) attack.

The vulnerability exists due to mishandling of PEBS status in a PEBS record In intel_pmu_drain_pebs_nhm in arch/x86/events/intel/ds.c in the Linux kernel. A local user can trigger resource exhaustion and perform a denial of service (DoS) attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Linux kernel: before 5.11.9, 5.11.9

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External links
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=d88d05a9e0b6d9356e97129d4ff9942d765f46ea
https://bugzilla.redhat.com/show_bug.cgi?id=1941784

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.