SB2021112305 - Red Hat Enterprise Linux 8 update for kernel



SB2021112305 - Red Hat Enterprise Linux 8 update for kernel

Published: November 23, 2021 Updated: October 23, 2022

Security Bulletin ID SB2021112305
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities 2
Exploitation vector Adjecent network
Highest impact Code execution

Breakdown by Severity

Medium 50% Low 50%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 2 vulnerabilities.


1) Improper Initialization (CVE-ID: CVE-2021-20317)

CWE-ID: CWE-665 - Improper Initialization

CVSSv4: 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


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

The vulnerability exists due to improper initialization the Linux kernel. A corrupted timer tree causes the task wakeup to be missing in the timerqueue_add function in lib/timerqueue.c. A local user can run a specially crafted application to crash the kernel.


2) Buffer overflow (CVE-ID: CVE-2021-43267)

CWE-ID: CWE-119 - Memory corruption

CVSSv4: CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/U:Green


The vulnerability allows a remote attacker to compromise the affected system.

The vulnerability exists due to insufficient validation of user-supplied input in net/tipc/crypto.c in the Linux kernel. The Transparent Inter-Process Communication (TIPC) functionality allows remote attackers to exploit insufficient validation of user-supplied sizes for the MSG_CRYPTO message type.

A remote attacker can send specially crafted MSG_CRYPTO messages to the affected system, trigger memory corruption and execute arbitrary code on the system.


Remediation

Install update from vendor's website.