XXE via MitM / Malicious Server in IscheduleClient

[prodigysml]

The Issue

An XML External Entity attack is a type of attack against an application that parses XML input. This attack occurs when XML input containing a reference to an external entity is processed by a weakly configured XML parser. This attack may lead to the disclosure of confidential data, denial of service, server side request forgery, port scanning from the perspective of the machine where the parser is located, and other system impacts.

Where the Issue Occurred

bw-calendar-engine/bw-calendar-engine-impl/src/main/java/org/bedework/calsvc/scheduling/hosts/IscheduleClient.java

Line 422 in 6c99a07

return builder.parse(new InputSource(new InputStreamReader(in)));

Remediation

https://www.owasp.org/index.php/XML_External_Entity_(XXE)_Prevention_Cheat_Sheet

[NicoleG25]

Hi, do you plan to address this vulnerability? :)
Note that it appears CVE-2018-1000836 was assigned to this issue.