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.