Ghostwriter Targets Ukraine Government Entities with Prometheus Phishing Malware
May 22, 2026
Malware / Artificial Intelligence
The Belarus-aligned threat actor known as Ghostwriter (aka UAC-0057 and UNC1151Ukraine's National Security and Defense Council) has been observed using lures related to Prometheus, a Ukrainian online learning platform, to target government organizations in the country. The activity, per the Computer Emergency Response Team of Ukraine (CERT-UA), involves sending phishing emails to government entities using compromised accounts. It's been active since the spring of 2026. "Typically, the email contains a PDF attachment with a link that, when clicked, leads to the download of a ZIP archive containing a JavaScript file," the agency said in a Thursday report. The JavaScript file, dubbed OYSTERFRESH, is designed to display a decoy document as a distraction mechanism, while stealthily writing an obfuscated and encrypted payload called OYSTERBLUES to the Windows Registry, as well as downloading and launching OYSTERSHUCK, which is responsible for decoding OYSTERBLUES. ...