In "Cuba, The Exchange of Intelligence Concerning Communist Subversive Activities - First Draft", part of the Califano Series (Box 3, Folder 10) within the JFK Assassination Files authorized for release in 2018, author V.H. Krulak sends the Service, OSD, and Joint Staff with Secret classification on March 13, 1963.
On page 6 Krulak writes that the U.S. Army, "through its attaches, currently has an informal arrangement involving bilateral exchanges of intelligence with Argentina, Colombia, Ecuador, Uruguay, Peru, Paraguay, and Venezuala. Information provided by the Army has been concerned with subversive personalities, communist infiltration, weapons movements and related matters."
This report came about eight months prior to JFK's assassination. I do not know the significance of this report, but you can help unravel this by searching "communist infiltration" on Project Apario. Or simply go here (to view search results for "communist infiltration").
The 45th President of the United States authorized the release of the JFK files which were previously set for declassification by Congress in the 1990s. Why it took decades for them to be released, and why when the National Archives did release them, the public found them less than ideal from the perspective of searching the documents, is anyone's guess. Project Apario has made the JFK assassination files available and searchable for free to the public.