Researchers have exposed a new targeted email campaign aimed at French entities in the construction, real estate, and government sectors that leverages the Chocolatey Windows package manager to deliver a backdoor called Serpent on compromised systems.
Enterprise security firm Proofpoint attributed the attacks to a likely advanced threat actor based on the tactics and the victimology patterns observed. The ultimate objective of the campaign remains presently unknown.
“The threat actor attempted to install a backdoor on a potential victim’s device, which could enable remote administration, command and control (C2), data theft, or deliver other additional payloads,” Proofpoint researchers said in a report shared with The Hacker News.
The phishing lure that triggers the infection sequence makes use of a resume-themed subject line, with the attached macro-embedded Microsoft Word document masquerading as information related to the European Union’s General Data Protection Regulation (GDPR).
Enabling the macros results in its execution, which retrieves a seemingly harmless image file hosted on a remote server but actually contains a Base64-encoded PowerShell script that’s obscured using steganography, a little-used method of concealing malicious code within an image or audio in order to circumvent detection.
images from Hacker News