CQ version

Even if this information is available at some location in the JCR, it is not advised to use read from there. The official API is the ProductInfo, and any other way to to determine the product version might just works by incidence.

Jörg

There is a ReST endpoint at /libs/granite/operations/content/systemoverview/export.json. This is used from the operations dashboard. It exposes the product info as well.

For AEM 6.5 - programatically we can get the aem product version using below:

com.adobe.granite.license.ProductInfoProvider; 
com.adobe.granite.license.ProductInfo;

@OSGiService
private ProductInfoProvider productInfoProvider;

ProductInfo productInfo = productInfoProvider.getProductInfo(); 
productInfo.getVerion().toString(); //6.5.13.0
productInfo.getShortVersion(); //6.5