GHSA-4j9x-g4x8-vcmf: ZendFramework potential XML eXternal Entity injection vectors

Zend_Feed_Rss and Zend_Feed_Atom were found to contain potential XML eXternal Entity (XXE) vectors due to insecure usage of PHP’s DOM extension. External entities could be specified by adding a specific DOCTYPE element to feeds; exploiting this vulnerability could coerce opening arbitrary files and/or TCP connections.

A similar issue was fixed for 1.11.13 and 1.12.0, in the Zend_Feed::import() factory method; however, the reporter of the issue discovered that the individual classes contained similar functionality in their constructors which remained vulnerable.