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Insights and research from our global cybersecurity team.

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Sifting through the spines: identifying (potential) Cactus ransomware victims

Authored by Willem Zeeman and Yun Zheng Hu This blog is part of a series written by various Dutch cyber security firms that have collaborated on the Cactus ransomware group, which exploits Qlik Sense servers for initial access. To view all of them please check the central blog by Dutch special interest group Cyberveilig Nederland […]


Android Malware Vultur Expands Its Wingspan

Authored by Joshua Kamp Executive summary The authors behind Android banking malware Vultur have been spotted adding new technical features, which allow the malware operator to further remotely interact with the victim’s mobile device. Vultur has also started masquerading more of its malicious activity by encrypting its C2 communication, using multiple encrypted payloads that are […]


The Spelling Police: Searching for Malicious HTTP Servers by Identifying Typos in HTTP Responses

At Fox-IT (part of NCC Group) identifying servers that host nefarious activities is a critical aspect of our threat intelligence. One approach involves looking for anomalies in responses of HTTP servers. Sometimes cybercriminals that host malicious servers employ tactics that involve mimicking the responses of legitimate software to evade detection. However, a common pitfall of […]


“We wait, because we know you.” Inside the ransomware negotiation economics.

Pepijn Hack, Cybersecurity Analyst, Fox-IT, part of NCC Group Zong-Yu Wu, Threat Analyst, Fox-IT, part of NCC Group Abstract Organizations worldwide continue to face waves of digital extortion in the form of targeted ransomware. Digital extortion is now classified as the most prominent form of cybercrime and the most devastating and pervasive threat to functioning […]


TA505: A Brief History Of Their Time

Threat Intel Analyst: Antonis Terefos (@Tera0017)Data Scientist: Anne Postma (@A_Postma) 1. Introduction TA505 is a sophisticated and innovative threat actor, with plenty of cybercrime experience, that engages in targeted attacks across multiple sectors and geographies for financial gain. Over time, TA505 evolved from a lesser partner to a mature, self-subsisting and versatile crime operation with […]


WastedLocker: A New Ransomware Variant Developed By The Evil Corp Group

Authors: Nikolaos Pantazopoulos, Stefano Antenucci (@Antelox), Michael Sandee and in close collaboration with NCC’s RIFT. About the Research and Intelligence Fusion Team (RIFT):RIFT leverages our strategic analysis, data science, and threat hunting capabilities to create actionable threat intelligence, ranging from IOCs and detection capabilities to strategic reports on tomorrow’s threat landscape. Cyber security is an […]


LDAPFragger: Bypassing network restrictions using LDAP attributes

Introduction A while back during a penetration test of an internal network, we encountered physically segmented networks. These networks contained workstations joined to the same Active Directory domain, however only one network segment could connect to the internet. To control workstations in both segments remotely with Cobalt Strike, we built a tool that uses the […]


Spectre and Meltdown: What you Need to Know

In the first days of 2018, a number of vulnerabilities were disclosed that are present in many modern-day CPUs. In this blog post we address the most frequently asked questions about Spectre and Meltdown with a focus on providing you with actionable guidance about what to do. This post is in addition to our webinar […]