Nullsoft Scriptable Install System (NSIS) before 3.09 mishandles access control for an uninstaller directory.
NSIS (Nullsoft Scriptable Install System) 3.06.1 before 3.12 sometimes uses the Low IL temp directory when executing as SYSTEM, allowing local attackers to gain privileges (if they can cause myGetTempFileName to return 0, as shown in the references).