SB2019051711 - Credentials management in Freedesktop systemd
Published: May 17, 2019 Updated: August 8, 2020
Security Bulletin ID
SB2019051711
CSH Severity
High
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Remote access
Highest impact
Code execution
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Credentials management (CVE-ID: CVE-2018-20839)
CWE-ID: CWE-255 - Credentials Management
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber
The vulnerability allows a remote non-authenticated attacker to execute arbitrary code.
systemd 242 changes the VT1 mode upon a logout, which allows attackers to read cleartext passwords in certain circumstances, such as watching a shutdown, or using Ctrl-Alt-F1 and Ctrl-Alt-F2. This occurs because the KDGKBMODE (aka current keyboard mode) check is mishandled.
Remediation
Install update from vendor's website.