This attack could pose a serious security threat. You should take immediate action to stop any damage or prevent further damage from happening.
This signature detects Venom attack that allows the remote attacker to perform various malicious actions on the compromised computer.
Upon visiting the infected website, visitors are redirected to a malicious site which runs a fingerprinting script. If the visitor is of interest, then the next time the visitor arrives on the infected website their computer may be sent a malicious payload.