How Tortoiseshell created a fake veteran hiring website to host malware

By Warren Mercer and Paul Rascagneres with contributions from Jungsoo An. Introduction Cisco Talos recently discovered a threat actor attempting to take advantage of Americans who may be seeking a job, especially military veterans. The actor, previously identified by Symantec as Tortoiseshell,...

Open Document format creates twist in maldoc landscape

By Warren Mercer and Paul Rascagneres. Introduction Cisco Talos recently observed attackers changing the file formats they use in an attempt to thwart common antivirus engines. This can happen across other file formats, but today, we are showing a change of approach for an actor who has deemed...

DNSpionage brings out the Karkoff

Warren Mercer and Paul Rascagneres authored this post. Update 4/24: The C2 section below now includes details around the XOR element of the C2 communication system. Executive summary In November 2018, Cisco Talos discovered an attack campaign, called DNSpionage, in which threat actors created a n...