Arch Linux Security Advisory ASA-202011-8 ========================================= Severity: Medium Date : 2020-11-10 CVE-ID : CVE-2020-28049 Package : sddm Type : privilege escalation Remote : No Link : https://security.archlinux.org/AVG-1266 Summary ======= The package sddm before version 0.19.0-1 is vulnerable to privilege escalation. Resolution ========== Upgrade to 0.19.0-1. # pacman -Syu "sddm>=0.19.0-1" The problem has been fixed upstream in version 0.19.0. Workaround ========== None. Description =========== A local privilege escalation has been discovered in the sddm display manager < 0.19.0. If the auth file is empty, X allows any local application (= any user on the system) to connect. This is currently the case until X wrote the display number to sddm and sddm used that to write the entry into the file. Impact ====== A local user might be able to escalate privileges. References ========== https://www.openwall.com/lists/oss-security/2020/11/04/2 https://github.com/sddm/sddm/commit/be202f533ab98a684c6a007e8d5b4357846bc222 https://security.archlinux.org/CVE-2020-28049