CVE-2026-9661: Postecert FIRMAOK! 1.6.29 Local Privilege Escalation via OpenSSL Search Path

Poste Italiane Postecert FIRMAOK! 1.6.29 on Windows contains a local privilege escalation vulnerability caused by an uncontrolled OpenSSL search path, where launcher.exe and dependent executables such as updater.exe and tslupdater.exe load OpenSSL configuration and library files from a hardcoded, user-writable directory that does not exist by default. A low-privileged local attacker can create this missing directory and place malicious OpenSSL configuration or library files inside it, causing the application to load and execute attacker-controlled code with the privileges of the user running it, enabling horizontal or, when a higher-privileged user runs the application, vertical privilege escalation up to full system compromise.