A malicious email campaign against Russian-speaking enterprises is employing a combination of exploits and Windows components to deliver a new backdoor that allows attackers to take over the affected system. The attack abuses various legitimate Windows components to run unauthorized scripts; this is meant to make detection and blocking more challenging, particularly by whitelisting-based solutions.

We’ve observed at least five runs from June 23 to July 27, 2017, each of which sent several malicious emails per target. Affected industries were financial institutions, including banks, and mining firms. Of note is how the attackers diversified their tactic—sending different emails for each run, per target.