"PATCHED Nitro Pro Enterprise" usually refers to a version of Nitro’s PDF software that has been modified by a third party to bypass its official licensing and activation systems [1, 2]. The specific version you mentioned— 12.4.0.259 (x86/x64)
Validate the digital signature of the installer to ensure it has not been tampered with. specific CVE security vulnerabilities fixed in this version? PATCHED Nitro Pro Enterprise 12.4.0.259 -x86x64- High