CVE-2021-45492: Incorrect Permission Assignment for Critical Resource

In Sage 300 ERP (formerly accpac) through 6.8.x, the installer configures the C:\Sage\Sage300\Runtime directory to be the first entry in the system-wide PATH environment variable. However, this directory is writable by unprivileged users because the Sage installer fails to set explicit permissions and therefore inherits weak permissions from the C:\ folder. Because entries in the system-wide PATH variable are included in the search order for DLLs, an attacker could perform DLL search-order hijacking to escalate their privileges to SYSTEM. Furthermore, if the Global Search or Web Screens functionality is enabled, then privilege escalation is possible via the GlobalSearchService and Sage.CNA.WindowsService services, again via DLL search-order hijacking because unprivileged users would have modify permissions on the application directory. Note that while older versions of the software default to installing in %PROGRAMFILES(X86)% (which would allow the Sage folder to inherit strong permissions, making the installation not vulnerable), the official Sage 300 installation guides for those versions recommend installing in C:\Sage, which would make the installation vulnerable.