ManageEngine Applications Manager 12 and 13 is vulnerable to privilege escalation due to improper restriction of an XML external entity

Summary

ManageEngine Applications Manager 12 and 13 before build 13690 allows an authenticated user, who is able to access /register.do page (most likely limited to administrator), to browse the filesystem and read the system files, including Applications Manager configuration, stored private keys, etc. By default Application Manager is running with administrative privileges, therefore it is possible to access every directory on the underlying operating system.