IBM API Connect 10.0.0.0 through 10.0.5.0, 10.0.1.0 through 10.0.1.7, and 2018.4.1.0 through 2018.4.1.20 is vulnerable to External Service Interaction attack, caused by improper validation of user-supplied input. A remote attacker could exploit this vulnerability to induce the application to perform server-side DNS lookups or HTTP requests to arbitrary domain names. By submitting suitable payloads, an attacker can cause the application server to attack other systems that it can interact with. IBM X-Force ID: 230264.

IBM API Connect is vulnerable to HTTP header injection, caused by improper validation of input by the HOST headers. This could allow an attacker to conduct various attacks against the vulnerable system, including cross-site scripting, cache poisoning or session hijacking.