Profiling Whonix

By Richard Bejtlich, Principal Security Strategist, Corelight Introduction This week I read a story announcing that the latest edition of Whonix had been released. I had heard of Whonix, but had never tried it. I knew it was a Linux distribution that tried to make it as easy and safe as possible to anonymize online […]

Investigating the Effects of TLS 1.3 on Corelight Logs, Part 3

By Richard Bejtlich, Principal Security Strategist, Corelight Introduction Welcome to part 3 of my three-part series on TLS. In the previous two articles I briefly introduced TLS, and showed how Corelight would produce logs for a clear-text HTTP session. I then performed the same transaction using TLS 1.2, and compared the logs with those seen […]

Investigating the Effects of TLS 1.3 on Corelight Logs, Part 2

By Richard Bejtlich, Principal Security Strategist, Corelight Introduction Welcome to part 2 of my three-part series on TLS. In the previous article I briefly introduced TLS, and showed how Corelight would produce logs for a clear-text HTTP session. In this article I will perform the same transaction using TLS 1.2, and compare the logs with […]

How to Use Corelight and Zeek Logs to Mitigate RDS/RDP Vulnerabilities

By Richard Bejtlich, Principal Security Strategist, Corelight Introduction On May 14 Microsoft released patches for, and details about, a remote code execution vulnerability in Remote Desktop Services (RDS), the graphical interactive desktop offered with most Windows operating system platforms. This vulnerability bears the Common Vulnerabilities and exposures number CVE-2019-0708. Remote Desktop Protocol (RDP) is the […]

Zeek is much more than a data format

By Greg Bell, CEO at Corelight Last week, a candidate for a senior role at Corelight explained his motivation for joining the company this way: “the world is standardizing on Zeek.”   And it’s true. The Zeek network security monitoring platform, created by leading researcher and Corelight co-founder Vern Paxson, is having its moment. Thousands of organizations worldwide […]

Examining aspects of encrypted traffic through Zeek logs

By Richard Bejtlich, Principal Security Strategist, Corelight In my last post I introduced the idea that analysis of encrypted HTTP traffic requires different analytical models. If you wish to preserve the encryption (and not inspect it via a middlebox), you have to abandon direct inspection of HTTP payloads to identify normal, malicious, and suspicious activity. […]