Zenoss Core through 5 Beta 3 does not properly detect recursion during entity expansion, which allows remote attackers to cause a denial of service (memory and CPU consumption) via a crafted XML document containing a large number of nested entity references, aka ZEN-15414, a similar issue to CVE-2003-1564.
https://docs.google.com/spreadsheets/d/1dHAc4PxUbs-4Dxzm1wSCE0sMz5UCMY6SW3PlMHSyuuQ/edit?usp=sharing