Hackers now use ZIP file concatenation to evade detection

Hackers are exploiting ZIP file concatenation to deliver malicious payloads on Windows machines without detection. This technique leverages how different ZIP parsers handle concatenated files. Researchers from Perception Point discovered a phishing attack using this method, where the malicious payload was hidden in one of the concatenated ZIPs and disguised as a legitimate file. Security solutions supporting recursive unpacking and treating emails with ZIP attachments suspiciously are recommended as defensive measures.