Unit 42 researchers have been tracking phishing campaigns that use PhantomVAI Loader to deliver information-stealing malware through a multi-stage, evasive infection chain. Threat actors wage these campaigns to deliver obfuscated scripts and loaders that use steganography techniques to conceal payloads. The loader initially used in these campaigns was dubbed Katz Stealer Loader, for the Katz Stealer malware that it delivers. Hackers are selling this new infostealer on underground forums as malware as a service (MaaS). Recently, we observed that the loader now delivers additional infostealers, such as AsyncRAT, XWorm, FormBook and DCRat. Given this unique behavior, we now track the loader under a new name: PhantomVAI Loader. We chose the name because of the loader’s stealth and the VAI…