SB2021052027 - Red Hat Enterprise Linux 8 update for systemd
Published: May 20, 2021
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 2 vulnerabilities.
1) Permissions, Privileges, and Access Controls (CVE-ID: CVE-2019-3842)
CWE-ID: CWE-264 - Permissions, Privileges, and Access Controls
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to pam_systemd creates a user session using environmental parameters. A local user can spoof an active session and gain additional PolicyKit privileges.
2) Input validation error (CVE-ID: CVE-2020-13776)
CWE-ID: CWE-20 - Improper input validation
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:U/U:Clear
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to systemd mishandles numerical usernames such as ones composed of decimal digits or 0x followed by hex digits, as demonstrated by use of root privileges when privileges of the 0x0 user account were intended.
Remediation
Install update from vendor's website.