From ERMAC to Hook: Investigating the technical differences between two Android malware variants

Authored by Joshua Kamp (main author) and Alberto Segura. Summary Hook and ERMAC are Android based malware families that are both advertised by the actor named “DukeEugene”. Hook is the latest variant to be released by this actor and was first announced at the start of 2023. In this announcement, the actor claims that Hook … Continue reading From ERMAC to Hook: Investigating the technical differences between two Android malware variants

Approximately 2000 Citrix NetScalers backdoored in mass-exploitation campaign

Fox-IT (part of NCC Group) has uncovered a large-scale exploitation campaign of Citrix NetScalers in a joint effort with the Dutch Institute of Vulnerability Disclosure (DIVD). An adversary appears to have exploited CVE-2023-3519 in an automated fashion, placing webshells on vulnerable NetScalers to gain persistent access. The adversary can execute arbitrary commands with this webshell, … Continue reading Approximately 2000 Citrix NetScalers backdoored in mass-exploitation campaign

From Backup to Backdoor: Exploitation of CVE-2022-36537 in R1Soft Server Backup Manager

Blog updated on 3 March 2023 to (i) remove a table containing data created on 09-01-23, more than one month earlier than publication of the original blog on 22-02-23 entitled ‘Backdoored ConnectWise R1Soft Server Backup Manager by Autonomous System Organization (Top 20 as of 2023-01-09)’; (ii) update a table containing data created on 09-01-23 entitled … Continue reading From Backup to Backdoor: Exploitation of CVE-2022-36537 in R1Soft Server Backup Manager

CVE-2022-27510, CVE-2022-27518 – Measuring Citrix ADC & Gateway version adoption on the Internet

Authored by Yun Zheng Hu Recently, two critical vulnerabilities were reported in Citrix ADC and Citrix Gateway; where one of them was being exploited in the wild by a threat actor. Due to these vulnerabilities being exploitable remotely and given the situation of past Citrix vulnerabilities, RIFT started to research on how to identify the … Continue reading CVE-2022-27510, CVE-2022-27518 – Measuring Citrix ADC & Gateway version adoption on the Internet

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