VERY IMPORTANT

Last month at the CERT-EU Conference in Brussels, Belgium, Volexity gave a presentation on a recent evolution in how attackers are maintaining persistence within victim networks. The method, which involves modifying the login pages to Cisco Clientless SSL VPNs (Web VPN), is both novel and surprisingly obvious at the same time. Attackers have been able to successfully implant JavaScript code on the login pages that enables them to surreptitiously steal employee credentials as they login to access internal corporate resources.