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Alma Linux: CVE-2021-3489: Moderate: kernel security, bug fix, and enhancement update (ALSA-2021-4356)

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Alma Linux: CVE-2021-3489: Moderate: kernel security, bug fix, and enhancement update (ALSA-2021-4356)

Severity
7
CVSS
(AV:L/AC:L/Au:N/C:C/I:C/A:C)
Published
06/04/2021
Created
05/05/2022
Added
05/04/2022
Modified
05/13/2022

Description

The eBPF RINGBUF bpf_ringbuf_reserve() function in the Linux kernel did not check that the allocated size was smaller than the ringbuf size, allowing an attacker to perform out-of-bounds writes within the kernel and therefore, arbitrary code execution. This issue was fixed via commit 4b81ccebaeee ("bpf, ringbuf: Deny reserve of buffers larger than ringbuf") (v5.13-rc4) and backported to the stable kernels in v5.12.4, v5.11.21, and v5.10.37. It was introduced via 457f44363a88 ("bpf: Implement BPF ring buffer and verifier support for it") (v5.8-rc1).

Solution(s)

  • alma-upgrade-kernel-tools-libs-devel

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