Researchers Discover New “PDFSider” Malware Used to Breach Major Enterprises with Advanced Techniques
37/69 Wednesday, January 21, 2026 Cybersecurity researchers from Resecurity have identified a new malware strain named PDFSider while investigating a security incident at a Fortune 100 financial company. The malware has reportedly been used by multiple threat actors-including the Qilin ransomware group-to gain initial access and maintain long-term persistence within compromised environments. The attack chain […]
