Permissions, Privileges, and Access Controls in systemd - CVE-2019-3844
Published: January 29, 2020
Vulnerability identifier: #VU24717
CSH Severity: Low
CVSS v4.0: 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
CVE-ID: CVE-2019-3844
CWE-ID: CWE-264
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: Freedesktop.org
Affected software:
systemd
systemd
Detailed vulnerability description
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to the systemd service that uses DynamicUser property can get new privileges through the execution of SUID binaries, which would allow to create binaries owned by the service transient group with the setgid bit set. A local user may use this flaw to access resources that will be owned by a potentially different service in the future, when the GID will be recycled.
How to mitigate CVE-2019-3844
Install updates from vendor's website.