HtmlUnit is a GUI-less browser for Java programs. HtmlUnit is vulnerable to Remote Code Execution (RCE) via XSTL, when browsing the attacker’s webpage. This vulnerability has been patched in version 3.9.0
Those using HtmlUnit to browse untrusted webpages may be vulnerable to Denial of service attacks (DoS). If HtmlUnit is running on user supplied web pages, an attacker may supply content that causes HtmlUnit to crash by a stack overflow. This effect may support a denial of service attack.This issue affects htmlunit before 2.70.0.