Adobe Reader X has over 150 known unpatched vulnerabilities. Hackers actively exploit these to install ransomware, keyloggers, or backdoors. Using it is like leaving your front door open.
Adobe Reader XI is many years old, and impossible to run on Big Sur. product Acrobat Reader DC from http://get.adobe.com/reader. Overview — Release Notes for Legacy Acrobat Products adberdr11010enusexe free
Writing an article promoting "free" downloads of old, unsupported software—especially executable files from non-official sources—poses significant security risks, including malware, ransomware, or exploiting unpatched vulnerabilities. Adobe Reader X has over 150 known unpatched vulnerabilities