Deserialization vulnerabilities are a class of bugs that have plagued multiple applications over the years, including Jira (CVE-2020-36239), Telerik (CVE-2019-18935), Jenkins (CVE-2016-9299), and more.
Attackers have leveraged these bugs for years to upload files, access unauthorized resources, and execute malicious code on targeted servers. Within the past 2 years, Mandiant has particularly observed APT41 using .NET ViewState and Java deserialization exploits to target companies and government entities within North America.
Researchers have already created tools for rapidly generating payloads. So, why not create a tool to rapidly generate detection and hunting rules?
In this talk, we will walk through the research process that led to HeySerial.py–a new rule generation tool–and we will show how we can use it to hunt for advanced attackers and potential zero-days.