Cidox
Overview
Executive Summary
Cidox (also heavily associated with the Rovnix family) is a highly sophisticated Bootkit and Trojan framework. Emerging in the early 2010s, Cidox was engineered for ultimate persistence and stealth, utilizing advanced kernel-level rootkit techniques to survive operating system reinstalls and bypass nearly all traditional security software. It was primarily utilized as an initial access and persistence mechanism to silently deploy highly lucrative banking trojans.Infection Vector and Technical Capabilities
Cidox was primarily distributed via drive-by downloads from exploit kits (like Blackhole or Nuclear) or embedded within pirated software (torrents and "warez" sites). Its execution represents the pinnacle of complex, low-level malware engineering:- Bootkit Persistence (MBR/VBR Infection): Unlike standard malware that hides in the registry, Cidox targets the fundamental boot process of the hard drive. It overwrites the Master Boot Record (MBR) or the Volume Boot Record (VBR). This guarantees that the malicious code executes *before* the Windows kernel or any antivirus software even loads into memory.
- Kernel-Mode Rootkit: Once the OS boots, the bootkit injects a malicious driver into the Windows kernel space (Ring 0). This rootkit intercepts system calls (API hooking), allowing Cidox to completely hide its files, registry keys, and active network connections from the user and security software.
- Payload Delivery (Banking Fraud): With absolute stealth achieved, the Cidox framework silently downloads and executes its primary payload—usually a sophisticated banking trojan designed to perform web injection and steal financial credentials.
Threat Assessment
The detection of a Cidox infection is a critical security failure. The presence of a bootkit indicates that the attacker has achieved absolute, unmitigated control over the endpoint. The malware operates below the visibility of the operating system, making standard forensic analysis incredibly difficult.Incident Response and Remediation
- Ineffectiveness of Standard AV: Traditional antivirus scans running within the infected OS cannot be trusted, as the kernel-mode rootkit will actively lie to the AV scanner about the state of the hard drive.
- Offline Eradication (Bare-Metal): The only reliable method to eradicate Cidox is a complete bare-metal wipe. The hard drive must be completely reformatted (including wiping the MBR/GPT partition tables) using offline media, and the operating system must be reinstalled from a known-secure image.
- Secure Boot (Prevention): The rise of UEFI and Microsoft's "Secure Boot" feature (which cryptographically verifies the bootloader before execution) has largely rendered MBR/VBR bootkits like Cidox obsolete on modern hardware. Ensure Secure Boot is strictly enabled in the BIOS/UEFI settings for all corporate endpoints.
Known aliases
Threat reports may refer to this family under multiple names:
MITRE ATT&CK Techniques
This family has been observed using the following ATT&CK techniques: T1542.003 T1014 T1055
Generated Detections (Boilerplate)
These YARA and Sigma rules are auto-generated based on the family name and aliases. They must be heavily tuned before deployment in a production environment.
YARA Rule
rule MALWARE_WIN_CIDOX {
meta:
description = "Detects Cidox (trojan)"
author = "SystemHelpdesk Boilerplate Generator"
date = "2026-07-06"
strings:
$s1 = "cidox" ascii wide nocase
$s2 = "rootkit.cidox" ascii wide nocase
$s3 = "trojan.rovnix" ascii wide nocase
$s4 = "bootkit.win32.cidox" ascii wide nocase
condition:
uint16(0) == 0x5a4d and any of them
}Sigma Rule
title: Suspicious Cidox Activity
id: 19768720d4060a8d1e553e5e7b6f4942
status: experimental
description: Detects generic indicators of the cidox malware family.
logsource:
category: process_creation
product: windows
detection:
selection:
Image|endswith:
- '\cmd.exe'
- '\powershell.exe'
CommandLine|contains:
- "*cidox*"
- "*rootkit.cidox*"
- "*trojan.rovnix*"
- "*bootkit.win32.cidox*"
condition: selection
level: mediumReferences & External Analysis
- Search "cidox" on VirusTotal (External Analysis)
Frequently Asked Questions
How do I remove the Cidox Trojan from Windows?
Manual removal of Cidox is highly discouraged as it may leave persistence mechanisms intact. We recommend disconnecting the device from the internet and utilizing a professional incident response service or enterprise-grade EDR software to conduct a full forensic sweep.
Is Cidox a virus or a Trojan?
Cidox is classified as a Trojan. Unlike traditional viruses that infect files, modern malware like Cidox typically operates as a standalone payload designed to compromise systems, steal data, or deploy secondary stage implants.
What are the main symptoms of a Cidox infection?
Symptoms of Cidox can include unexpected system slowness, unauthorized outbound network traffic to unknown IP addresses, disabled security software, and suspicious background processes running from AppData or Temp directories.
Related Families (Category: trojan)
Explore other malware families in the same category:
Protect Your Network Against Trojans
Want to prevent Cidox and similar threats from compromising your organization? Read our comprehensive defensive guide: Banking Trojan Protection.
Machine-readable
Get this profile as JSON: https://jordanricky1604-ship-it.github.io/malware-families-catalog/api/cidox.json
Ecosystem & Interactive Environments
This profile is part of the Malware Families Catalog, a public dataset of 2,899 malware families. The catalog is also published across our ecosystem: Hugging Face, Kaggle, Zenodo, Replit, StackBlitz, CodeSandbox, and CodePen.