TA453 Campaign Deploys Novel PowerShell Backdoor and Mac-Specific Malware

In mid-May 2023, threat actor TA453 targeted a US-based nuclear security expert affiliated with a foreign affairs think tank using deceptive emails. After initial contact, TA453 deployed a novel PowerShell backdoor, GorjolEcho, via cloud hosting providers. Upon realizing the target used a Mac, they sent another malicious email that delivered Mac-specific malware, NokNok. TA453 operates in support of Iran's Islamic Revolutionary Guard Corps (IRGC), specifically focusing on entities and individuals in the foreign affairs sector, particularly those dealing with Middle Eastern affairs and nuclear security.