Because Adobe no longer supports Acrobat XI, even a fully patched 11.0.23 version is susceptible to new "zero-day" exploits.
If you see 11.0.0 or 11.0.10, you are missing critical patches. You would need to manually apply the 11.0.23 patch (which Adobe no longer hosts officially, but is archived by third parties). adobe acrobat pro xi 11.0.23 included patched
One of the hallmark features of Pro XI is the ability to export PDFs to while preserving layout, columns, and formatting. Version 11.0.23 includes the final refinements to this OCR (Optical Character Recognition) engine. Because Adobe no longer supports Acrobat XI, even