If you still require this specific legacy version, you can typically find it through these official and archival channels: Official Adobe Sources Adobe FTP Server
Even the "Protected Mode" sandbox in Reader XI has known escape exploits that were patched in later versions but remain open in 11.0.23.
Adobe Acrobat Reader XI (11.0.23) is a legacy software version that reached its on October 15, 2017. Adobe no longer provides official direct downloads or security updates for this version, and it is strongly recommended to use the latest Adobe Acrobat Reader for security and compatibility with modern operating systems. Offline Installer Details (v11.0.23)
Are you installing this on a or managing an enterprise network ?
If you still require this specific legacy version, you can typically find it through these official and archival channels: Official Adobe Sources Adobe FTP Server
Even the "Protected Mode" sandbox in Reader XI has known escape exploits that were patched in later versions but remain open in 11.0.23.
Adobe Acrobat Reader XI (11.0.23) is a legacy software version that reached its on October 15, 2017. Adobe no longer provides official direct downloads or security updates for this version, and it is strongly recommended to use the latest Adobe Acrobat Reader for security and compatibility with modern operating systems. Offline Installer Details (v11.0.23)
Are you installing this on a or managing an enterprise network ?