Cryptredol

Overview

Ransomware:Win32/Cryptredol is a destructive malware strain with a dual-impact payload: it functions primarily as ransomware, encrypting victim data (`T1486`), but often includes a secondary cryptomining component (`T1496`) designed to monetize the system's hardware resources while the victim decides whether to pay the ransom. This dual-pronged attack maximizes the attacker's return on investment.

Understanding Cryptredol (Ransom-Miner)
To an end-user, the infection is catastrophic. Files become inaccessible, appended with a random extension, and the computer's fans spin loudly as the hidden miner consumes all available CPU power. For an organization, it requires immediate network isolation to prevent the rapid lateral spread of the encryption routine.

Execution and Dual-Payload Mechanics
Cryptredol is typically delivered via exploit kits or weaponized RDP access. Upon execution, it first disables Volume Shadow Copies (`vssadmin.exe delete shadows`) (`T1490`) to prevent easy data recovery. It then drops a secondary payload (often a variant of XMRig) to begin mining Monero (`T1496`) in the background. Simultaneously, it rapidly traverses local drives and mapped network shares, utilizing strong algorithms like AES or RSA to encrypt files (`T1486`). A ransom note is dropped in every affected directory.

Indicators of Compromise & Impact
The impact is total loss of data availability combined with severe system resource degradation. Host-based IoCs include the sudden renaming of thousands of files, the presence of ransom notes, EDR alerts for rapid file modification operations, and persistent 100% CPU utilization by unknown processes. System logs will show the execution of commands designed to inhibit system recovery. Network IoCs include connections to cryptocurrency mining pools (Stratum protocol) and a brief burst of traffic to a C2 server to transmit the victim's unique encryption ID.

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

Sigma Rule

title: Suspicious Cryptredol Activity
id: cdb308f34103bff8f4afb7d24c642b29
status: experimental
description: Detects generic indicators of the cryptredol malware family.
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        Image|endswith:
            - '\cmd.exe'
            - '\powershell.exe'
        CommandLine|contains:
            - "*cryptredol*"
    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 infected machine from the network immediately—pull the ethernet cable or disable the Wi-Fi adapter to stop the encryption from spreading to network shares.
2. Do not immediately reboot the machine; if the encryption process is active, rebooting may finalize the damage or destroy volatile memory keys.
3. Identify the initial infection vector (e.g., exposed RDP) to prevent further compromise.
4. Restore operations from known-good, offline backups; paying the ransom is highly discouraged as it funds criminal enterprises.

What to Avoid

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

1. Do not connect backup drives to the infected machine until it has been completely wiped and reimaged, as the ransomware will encrypt the backups.
2. Avoid assuming the threat is just a miner based on CPU usage; always check for encrypted files and dropped ransom notes.

References & External Analysis

• Search "cryptredol" on VirusTotal (External Analysis)

Frequently Asked Questions

Related Families (Category: ransomware)

Explore other malware families in the same category:

• Smalo
• Wuca
• Troxa
• Hezhi
• Scriptkd

Machine-readable

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