SB2021042135 - Red Hat Enterprise Linux 6 Extended Lifecycle Support update for kernel 

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Main Vulnerability Database SB2021042135

SB2021042135 - Red Hat Enterprise Linux 6 Extended Lifecycle Support update for kernel

Published: April 21, 2021 Updated: August 9, 2024

Security Bulletin ID SB2021042135
Severity
Low
Patch available
YES
Number of vulnerabilities 4
Exploitation vector Local access
Highest impact Code execution

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 4 secuirty vulnerabilities.


1) Improper locking (CVE-ID: CVE-2020-29661)

The vulnerability allows a local user to perform a escalate privileges on the system.

The vulnerability exists due to locking error in the tty subsystem of the Linux kernel in drivers/tty/tty_jobctrl.c. An local user can exploit this vulnerability to trigger a use-after-free error against TIOCSPGRP and execute arbitrary code with elevated privileges.


2) Resource exhaustion (CVE-ID: CVE-2021-20265)

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

The vulnerability exists due to application does not properly control consumption of internal resources in the unix_stream_recvmsg function in the Linux kernel when a signal was pending. A local user can trigger resource exhaustion and perform a denial of service (DoS) attack.


3) Permissions, Privileges, and Access Controls (CVE-ID: CVE-2021-27364)

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to iscsi_if_recv_msg() allows non-root users to connect and send commands to the Linux kernel. A local user can escalate privileges on the system.


4) Buffer overflow (CVE-ID: CVE-2021-27365)

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to a boundary error when processing Netlink messages in Linux kernel through 5.11.3, as certain iSCSI data structures do not have appropriate length constraints or checks, and can exceed the PAGE_SIZE value. A local unprivileged user can send a Netlink message that is associated with iSCSI, and has a length up to the maximum length of a Netlink message, trigger memory corruption and execute arbitrary code on the system with elevated privileges.


Remediation

Install update from vendor's website.

References