An attack or just a game? Corelight can help you tell the difference quickly

By Richard Bejtlich, Principal Security Strategist, Corelight When we think about using Corelight data, our mental models often fixate on finding evidence of suspicious and malicious activity. This makes sense, as network security monitoring data generated by Corelight and Zeek combines the granularity of high-fidelity traffic evidence with the compact features of storage-friendly data. However, […]

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 […]

Bring Network Security Monitoring to the Cloud with Corelight and Amazon VPC Traffic Mirroring

John Gamble, Director of Product Marketing, Corelight Corelight Sensors transform network traffic into comprehensive logs, extracted files, and custom insights via Zeek, a powerful, open-source network security monitoring framework used by thousands of organizations worldwide to accelerate incident response and unlock new threat hunting capabilities. While the sensors we’ve released to date have supported physical […]

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 […]

Investigating the Effects of TLS 1.3 on Corelight Logs, Part 1

By Richard Bejtlich, Principal Security Strategist, Corelight Introduction I’ve written previously about Corelight data and encryption. I wanted to know how TLS 1.3 would appear in Corelight data, and compare the same network conversation over clear-text HTTP, TLS 1.2, and TLS 1.3. In this first of three parts, I will introduce TLS and demonstrate a […]

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 […]

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. […]

Log enrichment with DNS host names

By Christian Kreibich, Senior Engineer, Corelight One of the first tasks for any incident responder when looking at network logs is to figure out the host names that were associated with an IP address in prior network activity. With Corelight’s 1.15 release we help automate the process and I would like to explain how this […]

Corelight’s recent contributions to open-source Bro

By Robin Sommer, CTO at Corelight and Bro development lead When we founded Corelight in 2013, one of our goals was to build an organization that could sustain open-source Bro development long term. At that time, the core team behind Bro was still funded primarily through grants from the National Science Foundation. One of the […]