SB2021111067 - Red Hat Enterprise Linux 8 update for the container-tools:rhel8 module



SB2021111067 - Red Hat Enterprise Linux 8 update for the container-tools:rhel8 module

Published: November 10, 2021

Security Bulletin ID SB2021111067
Severity
Medium
Patch available
YES
Number of vulnerabilities 2
Exploitation vector Remote access
Highest impact Denial of service

Breakdown by Severity

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

Description

This security bulletin contains information about 2 secuirty vulnerabilities.


1) Improper locking (CVE-ID: CVE-2021-20291)

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

The vulnerability exists due to double-locking error. When a container image is processed, each layer is unpacked using `tar`. If one of those layers is not a valid `tar` archive this causes an error leading to an unexpected situation where the code indefinitely waits for the tar unpacked stream, which never finishes. An attacker could use this vulnerability to craft a malicious image, which when downloaded and stored by an application using containers/storage, would then cause a deadlock leading to a Denial of Service (DoS).


2) Information disclosure (CVE-ID: CVE-2021-3602)

The vulnerability allows a remote attacker to gain access to potentially sensitive information.

The vulnerability exists due to podman build command with the --isolation chroot flag includes environment variables from the host. A remote attacker with access to the container can obtain sensitive information from environment variables.


Remediation

Install update from vendor's website.