CVE-2023-26604: High severity Systemd Project Systemd vulnerability
systemd before 247 does not adequately block local privilege escalation for some Sudo configurations, e.g., plausible sudoers files in which the "systemctl status" command may be executed. Specifically, systemd does not set LESSSECURE to 1, and thus other programs may be launched from the less program. This presents a substantial security risk when running systemctl from Sudo, because less executes as root when the terminal size is too small to show the complete systemctl output.
Credit
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
redhat/systemdto a version that resolves this vulnerability.Fixed in 247 - Upgrade
Upgrade
systemdto a version that resolves this vulnerability.Fixed in 247 - Configuration
Ensure systemd sets LESSSECURE=1 so that the less program prevents launching other programs when terminal size is too small to show complete output.
systemd (LESSSECURE environment handling) LESSSECURE = 1 - Compensating control
For sudo configurations that run systemctl (e.g., plausible sudoers entries for commands like "systemctl status"), limit sudo privileges so untrusted users cannot execute systemctl under sudo in a way that would trigger the less/LESSSECURE issue.
Event History
Frequently Asked Questions
What is the vulnerability ID of this issue?
The vulnerability ID of this issue is CVE-2023-26604.
What is the severity of CVE-2023-26604?
The severity of CVE-2023-26604 is high with a CVSS score of 7.8.
Which software is affected by CVE-2023-26604?
The systemd software version up to exclusive 247 is affected by CVE-2023-26604.
What does CVE-2023-26604 exploit?
CVE-2023-26604 exploits a local privilege escalation vulnerability in systemd for certain Sudo configurations.
How can I mitigate CVE-2023-26604?
To mitigate CVE-2023-26604, ensure that you are using systemd version 247 or later and monitor and update your Sudo configurations to block the exploit.