A new wave of cyber espionage has emerged, with Russian hackers deploying a sophisticated malware strain known as “Lostkeys” to infiltrate the systems of Western officials, journalists, and NGOs. According to researchers from Google’s Threat Intelligence Group, the malware is linked to Coldriver, also known as UNC4057, Star Blizzard, or Callisto—a threat actor believed to be part of Russia’s Federal Security Service (FSB), the successor to the KGB.
Coldriver has traditionally been involved in phishing operations to steal credentials, but the emergence of Lostkeys demonstrates a significant leap in their cyber capabilities.
Lostkeys appears to mark a shift in strategy for the group, moving beyond phishing and into deeper system infiltration. The malware is deployed in a targeted manner, reserved for high-value individuals such as political advisors, think tank members, journalists, and people with known connections to Ukraine.
Activity related to Lostkeys was observed by Google in the early months of 2024—specifically January, March, and April—with evidence suggesting its use might have started as far back as December 2023.
The attack begins with a deceptive Captcha page, tricking victims into copying a malicious PowerShell script into the Windows Run dialog. This method, known as “ClickFix,” bypasses typical security filters and exploits user behavior rather than software vulnerabilities.
Once executed, the script connects to a command-and-control server, downloading a series of payloads uniquely tailored to each victim.
In an effort to avoid detection, the malware includes anti-sandbox measures. During the second stage of infection, the script checks the screen resolution of the host machine and halts if it matches known virtual machine environments used by analysts and cybersecurity researchers. If the device passes this check, the malware proceeds to the final stage—a Visual Basic Script that steals data, including specific file types, system details, and active processes. These are exfiltrated back to the attackers using an encoded system that applies a unique two-key substitution cipher for each infected machine.
Lostkeys appears to be a more refined successor to a previous malware strain known as Spica, which Coldriver also deployed in 2024. While both strains focus on data exfiltration, Lostkeys features a more intricate delivery system and improved obfuscation techniques. Some earlier samples of Lostkeys mimicked legitimate software like Maltego and used executable files instead of PowerShell, though Google has not confirmed if these instances were part of the same campaign or the work of a different threat actor reusing Coldriver’s tactics.
This development highlights an alarming evolution in state-backed cyber operations, where advanced social engineering and stealth techniques are being increasingly used to infiltrate high-profile targets. As geopolitical tensions persist, the risks posed by such targeted cyber espionage campaigns are expected to grow.