An SSRF issue was discovered in Enghouse Web Chat 6.1.300.31. In any POST request, one can replace the port number at WebServiceLocation=http://localhost:8085/UCWebServices/ with a range of ports to determine what is visible on the internal network (as opposed to what general web traffic would see on the product's host). The response from open ports is different than from closed ports. The product does not allow one to change the protocol: anything except http(s) will throw an error; however, it is the type of error that allows one to determine if a port is open or not.

References

• https://nvd.nist.gov/vuln/detail/CVE-2019-16948
• https://mjlanders.com/2019/11/07/multiple-vulnerabilities-found-in-enghouse-zeacom-web-chat