Obsidium

Overview

VirTool:Win32/Obsidium is a critical heuristic detection utilized by antivirus engines to identify executables that have been heavily packed, encrypted, or obfuscated using the commercial Obsidium software protection system, a strong indicator of malware designed to evade static analysis.

Understanding Obsidium
For the end-user, an Obsidium alert means a highly suspicious file was blocked. For a malware analyst, an Obsidium detection is a red flag indicating a determined threat actor. While Obsidium is a legitimate commercial tool designed to protect intellectual property from reverse engineering, threat actors heavily abuse cracked or licensed versions to wrap their payloads (like ransomware, RATs, or banking trojans), effectively hiding the malicious code from signature-based antivirus engines.

Execution and Threat Hunting
The threat actor takes a compiled payload and wraps it in Obsidium. The resulting executable is highly entropic and densely packed. Obsidium operates by heavily encrypting the original executable code and embedding a decryption stub. When executed, the Obsidium stub runs first, employing significant anti-debugging, anti-dumping, and anti-VM techniques to ensure the environment is safe. If safe, it decrypts the malicious payload directly into memory. This makes static analysis virtually impossible. Threat hunters must recognize that an Obsidium alert means an advanced evasion technique was employed.

Forensic Analysis & Impact
The impact depends entirely on the hidden payload. Incident responders cannot rely on static analysis of the file on disk. EDR tools detect the execution by monitoring for behavioral anomalies once the packed payload decrypts and begins interacting with the OS. Memory forensics is absolutely required; the analyst must dump the RAM of the running process to extract the unencrypted payload, although Obsidium's robust anti-dumping features make this highly complex.

MITRE ATT&CK Techniques

Observed techniques used by this family, mapped to the MITRE ATT&CK framework:

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_OBSIDIUM {
    meta:
        description = "Detects Obsidium (ransomware)"
        author = "SystemHelpdesk Boilerplate Generator"
        date = "2026-07-06"
    strings:
        $s1 = "obsidium" ascii wide nocase
    condition:
        uint16(0) == 0x5a4d and any of them
}

Sigma Rule

title: Suspicious Obsidium Activity
id: 8c2a583b640cd8a3a3358a994966eb8b
status: experimental
description: Detects generic indicators of the obsidium malware family.
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        Image|endswith:
            - '\cmd.exe'
            - '\powershell.exe'
        CommandLine|contains:
            - "*obsidium*"
    condition: selection
level: medium

Containment & Response Steps

Ordered checklist for responders. Adapt to your environment and engage professional support for active incidents.

1. Isolate the endpoint immediately if the Obsidium executable was allowed to run; the highly obfuscated nature implies a severe, targeted payload.
2. If the process is active, capture a live memory image (RAM dump) before rebooting to attempt extraction of the decrypted payload.
3. Submit the packed binary to a specialized malware analyst for reverse engineering, noting that unpacking Obsidium is a highly specialized skill.
4. Perform a full forensic sweep to determine how the highly obfuscated executable arrived on the endpoint.

What to Avoid

Common mistakes during response to this family that can destroy evidence, spread the infection, or worsen recovery.

1. Do not waste time trying to statically analyze the Obsidium executable on disk; the strong encryption will yield zero actionable intelligence.
2. Avoid assuming the threat was fully blocked simply because AV flagged the file; the payload may have already executed in memory.

References & External Analysis

• Search "obsidium" on VirusTotal (External Analysis)

Frequently Asked Questions

Related Families (Category: ransomware)

Explore other malware families in the same category:

• Pasta
• Iczu
• Skillis
• Malwares
• Wigon

Machine-readable

Get this profile as JSON: https://jordan123234-malware-families-explorer.static.hf.space/api/obsidium.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.