ipl/web is a set of common web components for php projects. Prior to versions 0.13.1 and 0.10.3, the vulnerability allows an attacker to inject malicious Javascript into a victim's browser to run it in the context of Icinga Web. The victim needs to visit a specifically prepared website and may have no immediate chance to notice any wrongdoing. This issue has been patched in versions 0.13.1 and 0.10.3.
CWE-79