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 →

TA505 exploits SolarWinds Serv-U vulnerability (CVE-2021-35211) for initial access

NCC Group’s global Cyber Incident Response Team have observed an increase in Clop ransomware victims in the past weeks. The surge can be traced back to a vulnerability in SolarWinds Serv-U that is being abused by the TA505 threat actor. TA505 is a known cybercrime threat actor, who is known for extortion attacks using the … Continue reading TA505 exploits SolarWinds Serv-U vulnerability (CVE-2021-35211) for initial access →

Reverse engineering and decrypting CyberArk vault credential files

Author: Jelle Vergeer This blog will be a technical deep-dive into CyberArk credential files and how the credentials stored in these files are encrypted and decrypted. I discovered it was possible to reverse engineer the encryption and key generation algorithms and decrypt the encrypted vault password. I also provide a python implementation to decrypt the … Continue reading Reverse engineering and decrypting CyberArk vault credential files →

SnapMC skips ransomware, steals data

Over the past few months NCC Group has observed an increasing number of data breach extortion cases, where the attacker steals data and threatens to publish said data online if the victim decides not to pay. Given the current threat landscape, most notable is the absence of ransomware or any technical attempt at disrupting the … Continue reading SnapMC skips ransomware, steals data →

RM3 – Curiosities of the wildest banking malware

fumik0_ & the RIFT Team TL:DR Our Research and Intelligence Fusion Team have been tracking the Gozi variant RM3 for close to 30 months. In this post we provide some history, analysis and observations on this most pernicious family of banking malware targeting Oceania, the UK, Germany and Italy.  We’ll start with an overview of its origins and current operations before providing a deep dive technical analysis … Continue reading RM3 – Curiosities of the wildest banking malware →

Abusing cloud services to fly under the radar

tl;dr NCC Group and Fox-IT have been tracking a threat group with a wide set of interests, from intellectual property (IP) from victims in the semiconductors industry through to passenger data from the airline industry. In their intrusions they regularly abuse cloud services from Google and Microsoft to achieve their goals. NCC Group and Fox-IT … Continue reading Abusing cloud services to fly under the radar →

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 … Continue reading TA505: A Brief History Of Their Time →

StreamDivert: Relaying (specific) network connections

Author: Jelle Vergeer The first part of this blog will be the story of how this tool found its way into existence, the problems we faced and the thought process followed. The second part will be a more technical deep dive into the tool itself, how to use it, and how it works. Storytime About … Continue reading StreamDivert: Relaying (specific) network connections →