This indicates an attack attempt to exploit a HTML Injection vulnerability in Microsoft Internet Explorer.
The vulnerability is due to an error when the vulnerable software attempts to handle a maliciously crafted web page. An attacker can exploit this by tricking a user into visiting a malicious webpage and serve spoof contents to the unsuspecting user.
Internet Explorer 11
Information Spoofing: Remote attackers can serve spoof contents to unsuspecting targets.
Apply the most recent upgrade or patch from the vendor