Description

In June 2025, a cybercrime group stole $500,000 in cryptocurrency from a Russian blockchain developer by using a harmful extension in the Cursor AI development environment. This cybercrime shows the dangers of supply chain attacks on AI tools. The developer had recently installed a new operating system and was searching for a Solidity syntax highlighting extension in Cursor AI IDE. Even though the developer used online malware detection services and followed strict security measures, they accidentally installed a malicious package disguised as a legitimate tool. The fake extension, called "Solidity Language," had 54,000 downloads before it was discovered and removed. This attack was particularly dangerous because it used search ranking algorithms to appear above genuine alternatives. The attackers exploited the Open VSX registry's ranking system, which uses update dates, download counts, and ratings. By updating their malicious extension on June 15, 2025, they made it appear fourth in search results, while the legitimate extension, last updated on May 30, 2025, ranked eighth. The investigation showed the fake extension didn't provide syntax highlighting but acted as a dropper for a multi-stage attack. The first PowerShell script looked for ScreenConnect remote management software on the victim's computer. If it wasn't found, the malware downloaded another script to install ScreenConnect. This legitimate tool was set up to connect with the attackers' server at relay.lmfao[.]su, allowing ongoing access to the system. Using legitimate tools is a common tactic by advanced threat actors to hide malicious activities. Researchers discovered similar malicious packages, such as "solsafe" in the npm repository, along with three other Visual Studio Code extensions: solaibot, among-eth, and blankebesxstnion. All these used the same infection techniques and connected to the same command and control server.