cve/2019/CVE-2019-3842.md

CVE-2019-3842

Description

In systemd before v242-rc4, it was discovered that pam_systemd does not properly sanitize the environment before using the XDG_SEAT variable. It is possible for an attacker, in some particular configurations, to set a XDG_SEAT environment variable which allows for commands to be checked against polkit policies using the "allow_active" element rather than "allow_any".

POC

Reference

• http://packetstormsecurity.com/files/152610/systemd-Seat-Verification-Active-Session-Spoofing.html
• http://packetstormsecurity.com/files/152610/systemd-Seat-Verification-Active-Session-Spoofing.html
• https://www.exploit-db.com/exploits/46743/
• https://www.exploit-db.com/exploits/46743/

Github

• https://github.com/ARPSyndicate/cvemon