We have noticed a change of behaviour in the latest spam email campaigns used by Locky. Since its first release Locky took advantage of compromised domains to download the dropper binary, while recently Locky dropper is being delivered embedded into the loader code itself. By tracking these campaigns we have also noticed that Locky’s authors have made several attempts at embedding the dropper into the loader.
Dridex is currently one of the most active and widespread banking malwares. Like Locky ransomware also Dridex is dispatched through a massive spam mail campaign that uses the Necurs botnet. Our sensors have long been tracking these spam campaigns and recent captured emails contain a Word document that drops Dridex. In our latest samples we have observed a delay on execution of the downloader stage that wasn’t present before, we have further investigated to figure out whether Dridex’s authors were experimenting with new, even if basic, anti-sandbox techniques.