An issue was discovered in the Outlook add-in in Pronestor Planner before 8.1.77. There is local privilege escalation in the Health Monitor service because PronestorHealthMonitor.exe access control is mishandled, aka PNB-2359.

The Pronestor PNHM (aka Health Monitoring or HealthMonitor) add-in before 8.1.13.0 for Outlook has "BUILTIN\Users:(I)(F)" permissions for the "%PROGRAMFILES(X86)%\proNestor\Outlook add-in for Pronestor\PronestorHealthMonitor.exe" file, which allows local users to gain privileges via a Trojan horse PronestorHealthMonitor.exe file.