NetSight
IP …
high7.8

CVE-2021-3444

The bpf verifier in the Linux kernel did not properly handle mod32 destination register truncation when the source register was known to be 0.

Impact

The bpf verifier in the Linux kernel did not properly handle mod32 destination register truncation when the source register was known to be 0. A local attacker with the ability to load bpf programs could use this gain out-of-bounds reads in kernel memory leading to information disclosure (kernel memory), and possibly out-of-bounds writes that could potentially lead to code execution. This issue was addressed in the upstream kernel in commit 9b00f1b78809 ("bpf: Fix truncation handling for mod32 dst reg wrt zero") and in Linux stable kernels 5.11.2, 5.10.19, and 5.4.101.

Affected products

VendorProductAffected versions
LinuxLinux Kernel
before 5.4.101
from 5.5.0 before 5.10.19
from 5.11 before 5.11.2
DebianDebian Linux
Version 9.0
CanonicalUbuntu Linux
Versions 14.04, 16.04, 18.04, 20.04

Weakness classification

CWE-681CWE-125

References