The details of multiple, critical Pulse Secure SSL VPN vulnerabilities are well known; they were disclosed in detail by two security researchers as part of a talk at Black Hat USA 2019 on August 7, 2019. What has not been widely covered, but should come as no surprise, is that APT actors have been actively exploiting these vulnerabilities in order to gain access to targeted networks. The vulnerability being exploited is CVE-2019-11510, which allows a remote unauthenticated attacker to send specially crafted requests that allow read access of arbitrary files on the Pulse Secure VPN. This includes access to databases that the VPN server uses to track sessions, cleartext credentials, and NTLM hashes. Volexity has observed multiple attackers exploiting this vulnerability starting approximately a week after the talk was given. Volexity has worked on multiple incidents where networks, whose remote access is protected by two-factor authentication (2FA), have been intruded upon. […]