One Year Since Log4Shell: Lessons Learned for the next ‘code red’

Authored by Edwin van Vliet and Max Groot One year ago, Fox-IT and NCC Group released their blogpost detailing findings on detecting & responding to exploitation of CVE-2021-44228, better known as ‘Log4Shell’. Log4Shell was a textbook example of a code red scenario: exploitation was trivial, the software was widely used in all sorts of applications … Continue reading One Year Since Log4Shell: Lessons Learned for the next ‘code red’

I’m in your hypervisor, collecting your evidence

Authored by Erik Schamper Data acquisition during incident response engagements is always a big exercise, both for us and our clients. It’s rarely smooth sailing, and we usually encounter a hiccup or two. Fox-IT’s approach to enterprise scale incident response for the past few years has been to collect small forensic artefact packages using our … Continue reading I’m in your hypervisor, collecting your evidence

Sharkbot is back in Google Play

Authored by Alberto Segura (main author) and Mike Stokkel (co-author) Introduction After we discovered in February 2022 the SharkBotDropper in Google Play posing as a fake Android antivirus and cleaner, now we have detected a new version of this dropper active in the Google Play and dropping a new version of Sharkbot.This new dropper doesn't … Continue reading Sharkbot is back in Google Play

Detecting DNS implants: Old kitten, new tricks – A Saitama Case Study 

Max Groot & Ruud van Luijk TL;DR A recently uncovered malware sample dubbed ‘Saitama’ was uncovered by security firm Malwarebytes in a weaponized document, possibly targeted towards the Jordan government. This Saitama implant uses DNS as its sole Command and Control channel and utilizes long sleep times and (sub)domain randomization to evade detection. As no … Continue reading Detecting DNS implants: Old kitten, new tricks – A Saitama Case Study 

Flubot: the evolution of a notorious Android Banking Malware

Authored by Alberto Segura (main author) and Rolf Govers (co-author) Summary Flubot is an Android based malware that has been distributed in the past 1.5 years inEurope, Asia and Oceania affecting thousands of devices of mostly unsuspecting victims.Like the majority of Android banking malware, Flubot abuses Accessibility Permissions and Servicesin order to steal the victim's … Continue reading Flubot: the evolution of a notorious Android Banking Malware

Adventures in the land of BumbleBee

Authored by: Nikolaos Totosis, Nikolaos Pantazopoulos and Mike Stokkel Executive summary BUMBLEBEE is a new malicious loader that is being used by several threat actors and has been observed to download different malicious samples. The key points are: BUMBLEBEE is statically linked with the open-source libraries OpenSSL 1.1.0f, Boost (version 1.68). In addition, it is … Continue reading Adventures in the land of BumbleBee

SharkBot: a “new” generation Android banking Trojan being distributed on Google Play Store

Authors: Alberto Segura, Malware analystRolf Govers, Malware analyst & Forensic IT Expert NCC Group, as well as many other researchers noticed a rise in Android malware last year, especillay Android banking malware. Within the Treat Intelligence team of NCC Group we’re looking closely to several of these malware families to provide valuable information to our … Continue reading SharkBot: a “new” generation Android banking Trojan being distributed on Google Play Store

log4j-jndi-be-gone: A simple mitigation for CVE-2021-44228

tl;dr Run our new tool by adding -javaagent:log4j-jndi-be-gone-1.0.0-standalone.jar to all of your JVM Java stuff to stop log4j from loading classes remotely over LDAP. This will prevent malicious inputs from triggering the “Log4Shell” vulnerability and gaining remote code execution on your systems. In this post, we first offer some context on the vulnerability, the released fixes (and their shortcomings), and … Continue reading log4j-jndi-be-gone: A simple mitigation for CVE-2021-44228

Log4Shell: Reconnaissance and post exploitation network detection

Note: This blogpost will be live-updated with new information. NCC Group’s RIFT is intending to publish PCAPs of different exploitation methods in the near future – last updated December 14th at 13:00 UTC About the Research and Intelligence Fusion Team (RIFT): RIFT leverages our strategic analysis, data science, and threat hunting capabilities to create actionable threat … Continue reading Log4Shell: Reconnaissance and post exploitation network detection

Encryption Does Not Equal Invisibility – Detecting Anomalous TLS Certificates with the Half-Space-Trees Algorithm

Author: Margit Hazenbroek tl;dr An approach to detecting suspicious TLS certificates using an incremental anomaly detection model is discussed. This model utilizes the Half-Space-Trees algorithm and provides our security operations teams (SOC) with the opportunity to detect suspicious behavior, in real-time, even when network traffic is encrypted.  The prevalence of encrypted traffic As a company that … Continue reading Encryption Does Not Equal Invisibility – Detecting Anomalous TLS Certificates with the Half-Space-Trees Algorithm