File this one in the “Irony” department: Threat actors have been discovered trying to infect security-minded individuals with a trojan downloader by sending spear phishing emails that offer free invitations to Palo Alto Networks' Nov. 3 Cyber Security Summit in Jakarta, Indonesia.

Palo Alto Networks' Unit 42 threat research group identified the malware as the Emissary trojan, which is linked to Lotus Blossom, an advanced persistent threat (APT) group that has historically launched campaigns against multiple countries in Southeast Asia. According to a Palo Alto blog post, the trojan arrives as an malicious Word document attachment bearing the file name “[FREE INVITATIONS] CyberSecurity Summit.doc.” Opening the attachment deploys a decoy document and downloads Emissary, which compromises systems by exploiting a critical vulnerability in Microsoft's MSCOMCTL.OCX ActiveX controls  (CVE-2012-0158) that dates back to 2012.

By analyzing the original screenshot that was cropped to create the decoy document, Palo Alto found a variety of evidence suggesting that the adversaries' primarily language is Chinese.