Solving the Openfire Lab Blue team challenge

Solving the Openfire Lab Blue team challenge

Today we’re reviewing a vulnerability in Openfire. It is a self-hosted alternative to Slack/Teams: you run it on your own infrastructure, control the data, and extend it with plugins. As a cybersecurity analyst, you are tasked with investigating a data breach targeting your organization’s Openfire messaging server. Attackers have exploited a vulnerability in the server, compromising sensitive communications and potentially exposing critical data. Your task is to analyze the provided network capture files using Wireshark. Identify evidence of the exploitation, trace the attacker’s actions, and uncover indicators of compromise. ...

August 24, 2025 · 4 min
Solving the XLMRat Blue team challenge

Solving the XLMRat Blue team challenge

Today we’re looking at the XLMRat malware. It is a remote access trojan (hence the RAT part) built to be small, sneaky, and stupidly persistent. It typically rides in via phishing or social engineering, often disguised as something mundane, like a JPG or TXT file. It targets Windows systems and speaks fluent PowerShell. It’s popular among low-effort attackers looking for ready-made tools that still pack a punch. Especially in campaigns targeting individuals or small orgs where endpoint hygiene is weak. There’s a block with more information at the end of this post ⬇️ ...

June 28, 2025 · 6 min
Solving the BlueSky Ransomware Blue team challenge

Solving the BlueSky Ransomware Blue team challenge

Today we’re looking at the BlueSky ransomware, a strain of malicious software that encrypts files on a victim’s system, rendering them inaccessible until a ransom is paid. First detected in June 2022, it shares similarities with other notorious ransomware families like Conti and Babuk. BlueSky spreads through methods such as phishing emails, malicious links, and network protocols like SMB (port 445 TCP). Once inside a system, it uses advanced evasion techniques, such as hiding threads from debuggers, to avoid detection. It targets both files and processes, encrypting files with RSA encryption and adding the .bluesky extension to them while maintaining operational stability by avoiding critical system processes. ...

May 18, 2025 · 11 min
DanaBot blue team challenge

Solving the DanaBot Blue team challenge

In this blog post, we’ll walk through a Blue Team lab challenge hosted by CyberDefenders, specifically investigating a breach scenario involving DanaBot malware. The SOC team has detected suspicious activity in the network traffic, revealing that a machine has been compromised. Sensitive company information has been stolen. Your task is to use Network Capture (PCAP) files and Threat Intelligence to investigate the incident and determine how the breach occurred. The challenge is presented by CyberDefenders (https://cyberdefenders.org) and can be found here: https://cyberdefenders.org/blueteam-ctf-challenges/danabot. ...

May 4, 2025 · 5 min
WebStrike Blue Team Challenge

Solving the WebStrike Blue Team Challenge

The challenge In the intricate world of cybersecurity, every attack leaves behind digital footprints waiting to be deciphered. In this post, we embark on a brief journey to unravel a cyber threat, dissecting each element that reveals an attacker’s origin, tactics, and motives. Let’s dive in. The challenge is presented by CyberDefenders (https://cyberdefenders.org) and can be found here: https://cyberdefenders.org/blueteam-ctf-challenges/webstrike/. Note: This post is not sponsored by or affiliated with CyberDefenders. ...

December 17, 2023 · 4 min