CVE-2021-46993

HIGH

Linux Kernel < 5.4.120 - Out-of-Bounds Read

Title source: rule
STIX 2.1

Description

In the Linux kernel, the following vulnerability has been resolved: sched: Fix out-of-bound access in uclamp Util-clamp places tasks in different buckets based on their clamp values for performance reasons. However, the size of buckets is currently computed using a rounding division, which can lead to an off-by-one error in some configurations. For instance, with 20 buckets, the bucket size will be 1024/20=51. A task with a clamp of 1024 will be mapped to bucket id 1024/51=20. Sadly, correct indexes are in range [0,19], hence leading to an out of bound memory access. Clamp the bucket id to fix the issue.

Scores

CVSS v3 7.1
EPSS 0.0012
EPSS Percentile 30.6%
Attack Vector LOCAL
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-125
Status published
Products (1)
linux/linux_kernel 5.3 - 5.4.120
Published Feb 28, 2024
Tracked Since Feb 18, 2026