The newly discovered Clop ransomware attempts to remove Malwarebytes and other native security tools from the Windows machines it infects.
According to Bleeping Computer, security researcher and reverse engineer Vitali Kremez found that Clop ransomware ran a small program before initiating its encryption routine on an infected Windows machine. The purpose of the program was to disable numerous security tools running on the computer so that it could effectively encrypt a victim’s data.
For instance, the threat attempted to disable Windows Defender by configuring the Registry values so as to disable behavior monitoring, real-time protection and other security processes. These settings would return to normal if victims had Tamper Protection in Windows 10, however.
Clop, a variant of the CryptoMix ransomware family, also attempted to disable Malwarebytes’ standalone Anti-Rasomware product, which is now retired, using a command that sought to prevent the tool from restarting.
Not the First Threat to Target Windows Defender
Clop isn’t the first malware family that’s set its sights on Windows Defender. Back in July 2019, Bleeping Computer reported on a new variant of the TrickBot banking Trojan that attempted to disable security services and processes associated with Windows Defender.
That was just a few months before the computer self-help site covered GootKit, a banking Trojan that used UAC bypass and WMIC commands to prevent Windows Defender from specifically analyzing the malware executable. And in October 2019, Bleeping Computer shared Kremez’s findings on Novter, malware that used PowerShell to disable Windows Defender and modify the Windows Update settings.
How to Defend Against Clop Ransomware
Security professionals can help their organizations defend against Clop ransomware by investing in a security awareness training program that takes the different needs and security requirements of each user group into consideration. Doing so will allow the organization to strengthen its digital defenses against phishing campaigns and other common delivery vectors for ransomware. Security teams should leverage this training program as part of a layered defense strategy for ransomware, a concerted effort that should also include anti-spam, a backup strategy and other security measures.