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vulnerability

Alma Linux: CVE-2021-29155: Moderate: kernel security, bug fix, and enhancement update (ALSA-2021-4356)

Severity
2
CVSS
(AV:L/AC:L/Au:N/C:P/I:N/A:N)
Published
Apr 20, 2021
Added
May 4, 2022
Modified
Mar 31, 2026

Description

An issue was discovered in the Linux kernel through 5.11.x. kernel/bpf/verifier.c performs undesirable out-of-bounds speculation on pointer arithmetic, leading to side-channel attacks that defeat Spectre mitigations and obtain sensitive information from kernel memory. Specifically, for sequences of pointer arithmetic operations, the pointer modification performed by the first operation is not correctly accounted for when restricting subsequent operations.

Solution

alma-upgrade-kernel-tools-libs-devel
Title
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