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 […]

Network Security Monitoring, a Requirement for Managed Service Providers?

By Richard Bejtlich, Principal Security Strategist, Corelight Over the last six months, we’ve read in the security press about a variety of managed service providers (MSPs) being compromised by nation-state and criminal actors. Some examples: December 2018 – The United States Department of Justice indicted two individuals associated with APT10 for their role in compromising […]

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 […]

Is IPS a feature or a product?

By Richard Bejtlich, Principal Security Strategist, Corelight This post is a departure from previous editions. It is inspired by discussions I’ve had recently with a few different online and in-person communities. I will present my view on the topic, but I’m more interested in hearing what readers think! I’ve had a few conversations during the […]

First, Do No Harm

By Richard Bejtlich, Principal Security Strategist, Corelight When we hear the phrase “first, do no harm,” most of us think of the Hippocratic Oath and its guidance for physicians. I was surprised to learn that the phrase as translated does not actually appear in the Greek, and that the origins are more modern, dating from 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. […]

Network security monitoring is dead, and encryption killed it.

By Richard Bejtlich, Principal Security Strategist, Corelight This post is part of a multi-part series on encryption and network security monitoring. This post covers a brief history of encryption on the web and investigates the security analysis challenges that have developed as a result. I’ve been hearing this message since the late-2000s, and wrote a […]