The emails can be jarring, but the technique used by Qakbot (aka Qbot) seems to be especially convincing: The email-borne malware has a tendency to spread itself around by inserting malicious replies into the middle of existing email conversations, using the compromised accounts of other infection victims. These interjections in the form of a reply-all message include a short sentence, and a link to download a zip file containing a malicious office document, one that brings down the malware when someone opens it.