Security strategy for the next Log4Shell
Last week I had the privilege to be in Washington, DC talking to a group of defenders. I heard a clear pattern of words: “data-driven,” “telemetry-first,” and “visibility”.
Last week I had the privilege to be in Washington, DC talking to a group of defenders. I heard a clear pattern of words: “data-driven,” “telemetry-first,” and “visibility”.
We have published an initial blog on the Log4j exploit and a followup blog with a second detection method for detecting the first stage of exploits occurring over LDAP. Today, we will discuss a third detection method, this one focused on the second-stage download that happens after the first stage completes. In this case, the JVM will download additional Java code payloads over HTTP.
We recently discussed some methods for detecting the Log4j exploit, and we’ve now developed another method that everyone running Zeek® or a Corelight sensor can use. Our new approach is based on the rarity of legitimate downloads of Java via LDAP. Zeek does not currently have a native LDAP protocol analyzer (though one is available if you are running Spicy). This will not stop you from detecting this exploit downloading Java over LDAP, though. To see how, read on.
Security workers across the world have been busy since last Friday dealing with CVE-2021-44228, the log4j 0-day known as Log4Shell, that is already being heavily exploited across the Internet. Given the huge number of systems that embed the vulnerable library, the myriad ways that attackers can exploit the vulnerability, and the fact that automated exploitation has already begun, defenders should expect to be dealing with it for the foreseeable future.
CISA recently released a set of playbooks for the Federal Civilian Executive Branch (FCEB) to provide improved cybersecurity incident response (IR) and vulnerability response. As was demonstrated by the SolarWinds SUNBURST attack in December 2020, coordination and reporting across the FCEB continues to be a challenge. Adding to this challenge is the situation where agencies have differing playbooks on how to handle confirmed malicious cyber activity where a major incident has been identified.
What is the XDR paradox? It’s the hottest term in security but there is no consensus yet on the right definition. Why is that? Many organizations have deployed EDR and are benefiting from it, but also looking to the gaps that EDR can’t address such as unmanaged / compromised devices or network-centric TTPs. Likewise, many vendors of EDR/SIEM products have realized they have the same general workflow (analyze data, present an alert, triage it, etc).
On its surface, CVE-2021-42292 doesn’t look like the kind of vulnerability that a network-based tool can find reliably. Marked by Microsoft as a local file format vulnerability, security veterans would expect that between encryption and encoding, there would be a million different ways to evade network detection with a weaponized exploit.
One of the most common questions that Corelight customers and prospects who are using our Suricata integration ask is “what signatures should I run?” While our answer has always started with the industry-standard Emerging Threats Pro feed, we recognize that other feeds - like the ones from Crowdstrike or private industry groups - often make excellent additions to the ET Pro set.
When you hear the term “Internet of Things,” (IoT) do you picture home devices like lightbulbs, smart assistants, and wifi-connected refrigerators? Perhaps you think of enterprise devices like video conferencing systems, smart sensors, or security cameras? Or maybe traditional office equipment like VoIP phones, printers, and smart TVs come to mind. No matter what devices you imagine, IoT represents an ever-expanding attack surface.
Looking for some threat hunting and incident response practice that's more game than work? Check out the new Capture the Flag (CTF) challenges from Corelight, now available on Splunk’s Boss of the SOC (BOTS) website - just in time for.conf! Our two on-demand BOTS modules will show you how Corelight data in Splunk can accelerate your processes and help analysts spend more time analyzing and less time fumbling with queries and gluing together data sources.