This is Trend Micro detection for packets passing through HTTP network protocols that can be used as Command and Control Communication. This also indicates a malware infection. Below are some indicators of an infected host:
Excessive spamming, exploit attempts on hosts inside or outside the network, and denial of service (DoS) attacks on hosts outside the network, which often result in degraded network performance and further propagation of the malware.
Creating additional administrative accounts, creating new shared folders, and interfering with the operation of security software, resulting in a weakening of overall network security.
Keylogging and stealing of confidential data.
Sending massive amounts of unsolicited and sometimes fraudulent, malicious, and illegal email messages that may appear to originate from your domain.
Identify and clean threats with Rescue Disk, specific to suspected threats that are persistent or difficult-to-clean. Rescue Disk allows you to use a CD, DVD, or USB drive to examine your computer without launching Microsoft Windows.