As someone who has spent many years researching attacks and supporting incident response teams, I’ve seen one question come up again and again: How do we return to a verified clean state after an intrusion? In every ransomware case, in every targeted espionage...
Detecting NetScaler Compromise with THOR During CVE-2025-7775 Attacks
Citrix NetScaler appliances are under active attack through CVE-2025-7775 and related vulnerabilities. Even fully patched systems may already be compromised. This post explains how Nextron’s THOR provides agentless compromise detection with YARA and IOC scans — a proven method for identifying webshells, backdoors, and post-exploit artifacts.
Sindoor Dropper: New Phishing Campaign
Our analysis uncovered a phishing campaign targeting organizations in India, leveraging spear-phishing techniques reminiscent of Operation Sindoor. What makes this activity stand out is the use of a Linux-focused infection method that relies on weaponized .desktop...
When Best Practices Aren’t Enough: UK Breaches Underscore the Importance of Compromise Assessments
Despite extensive guidance from national authorities, several prominent UK organizations have recently suffered significant cyber attacks. Incidents at Colt Technology Services, Marks & Spencer, and Flutter Entertainment demonstrate that adherence to security...
Webhooks in THOR Cloud: Event-Driven Notifications and System Integration
We’re introducing Webhooks in THOR Cloud — a new feature that delivers event-driven notifications and facilitates integration with your existing systems. Webhooks allow you to subscribe to specific events and automatically receive event data as soon as those events...
Detecting the Most Popular MITRE Persistence Method – Registry Run Keys / Startup Folder
Persistence is a cornerstone tactic for both threat actors and red‑teamers, allowing them to cling to a compromised system even after reboots, credential resets, or other disruptions that might otherwise cut them off. MITRE ATT&CK places these activities in...
ToolShell Aftermath: What Defenders Should Do After Patching CVE-2025-53770
The recently exploited SharePoint vulnerability chain known as ToolShell (CVE-2025-53770) has shown once again that patching alone isn't enough. Attackers gained unauthenticated remote access to vulnerable on-premises SharePoint servers, planted web shells, and...
The Blind Spot Scanner – Why THOR Detects What Others Miss
Antivirus engines and EDRs have their place – no doubt. But what happens when malware simply slips through their nets? What if the malicious file was never executed? What if the incident happened months ago? That’s where THOR comes in. Our compromise assessment...
From THOR Scan to Timeline: Correlating Findings in Timesketch
We’ve released a CLI utility that converts THOR logs into a Timesketch-compatible format. This allows analysts to import and visualize THOR’s forensic findings as timestamped events on a unified timeline, together with data from other sources. The thor2ts utility...
Stealth in 100 Lines: Analyzing PAM Backdoors in Linux
Abuse of Modular Trust PAM (Pluggable Authentication Modules) is a fundamental part of Linux authentication infrastructure. Its flexibility - designed to support various authentication mechanisms - can be exploited by adversaries. In our analysis, we encountered a...
Nitrogen Dropping Cobalt Strike – A Combination of “Chemical Elements”
First detected in September 2024 and initially targeting the United States and Canada, the Nitrogen ransomware group has since expanded its reach into parts of Africa and Europe. Many of their victims remain absent from Nitrogen’s public ransomware blog and likely...
Active Exploitation of SAP NetWeaver Systems — Our Recommendation for Local Scans
In recent days, major security companies such as ReliaQuest and Onapsis have disclosed the active exploitation of CVE-2025-31324, a critical vulnerability in SAP NetWeaver’s Visual Composer component. The vulnerability allows unauthenticated attackers to upload...
End of Life Announcement for THOR Version 10.6
Nextron Systems officially announces the End of Life (EOL) and End of Support (EOS) for THOR version 10.6, our former stable forensic scanner version. Effective December 31, 2025, THOR 10.6 will no longer receive updates, maintenance, or technical support. Background...
Obfuscated Threats – The Invisible Danger in Cybersecurity
Obfuscation is a technique widely used by cybercriminals, Advanced Persistent Threat (APT) groups, and even red-teaming operations. APTs, in particular, rely on obfuscation to remain undetected within networks for extended periods. However, modern malware, ransomware,...
Protecting Outdated and Unsupported Systems
Security strategies often assume that systems can be patched, upgraded, or replaced. In reality, many critical environments operate on legacy platforms where these options are impractical. Industrial control networks, healthcare systems, and government infrastructure...












