Psyme
Overview
Executive Summary
Psyme is a classification for a family of malicious Trojans that rely heavily on scripting languages—specifically VBScript (.vbs) and JavaScript (.js)—to execute their payloads. Rather than using compiled executables (.exe), Psyme leverages the native Windows Script Host (WSH) to download and execute secondary malware, making it a frequent component in drive-by downloads and exploit kits.Infection Vector and Technical Capabilities
Psyme is predominantly distributed via malicious websites (where the script is embedded directly into the HTML and executed via a browser vulnerability) or as an obfuscated script file attached to a phishing email (e.g., an invoice disguised as a `.pdf.vbs` file). Upon execution, Psyme leverages native Windows tools:- Living off the Land (LotL): By executing via `wscript.exe` or `cscript.exe`, Psyme bypasses basic executable whitelisting and often avoids heuristic detection by older AV engines that focus solely on PE files.
- Downloader Functionality: The script's primary function is to reach out to an attacker-controlled server (often using the `MSXML2.XMLHTTP` COM object) to download a secondary, more destructive payload (like a banking trojan or ransomware).
- File System and Registry Manipulation: The script typically saves the downloaded payload to the `%Temp%` or `%AppData%` directory, modifies the Registry to ensure persistence (e.g., adding an entry to the `Run` key), and then executes the payload using the `WScript.Shell` object.
Threat Assessment
A Psyme infection is a severe indicator of compromise (IoC) because it acts as the gateway for more destructive malware. The use of script-based downloaders is a common tactic for bypassing initial perimeter defenses and delivering ransomware payloads.Remediation and Eradication
- Endpoint Detection and Response (EDR): EDR solutions must be configured to monitor the behavior of script interpreters (`wscript.exe`, `cscript.exe`, `powershell.exe`), particularly when they attempt to establish outbound network connections or execute files in temporary directories.
- Network Isolation and Sweeps: Isolate the infected endpoint and conduct a thorough forensic sweep to identify the specific secondary payload that Psyme successfully downloaded and executed.
- System Hardening (GPO): To prevent future script-based attacks, configure Group Policy (GPO) to change the default file association for `.vbs` and `.js` files to open in Notepad rather than executing via WSH, and deploy Windows Defender Application Control (WDAC).
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: T1059.005 T1059.007 T1105 T1547.001
Tactical Mitigations
Based on the techniques used by this family, consider the following defensive strategies:
- T1059.005: Restrict execution of scripting languages such as PowerShell, VBScript, or Python to authorized administrators. Enforce Script Block Logging.
- T1059.007: Restrict execution of scripting languages such as PowerShell, VBScript, or Python to authorized administrators. Enforce Script Block Logging.
- T1105: Implement network intrusion detection systems (NIDS) and host-based firewalls to block unauthorized inbound or outbound file transfers.
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_PSYME {
meta:
description = "Detects Psyme (ransomware)"
author = "SystemHelpdesk Boilerplate Generator"
date = "2026-07-06"
strings:
$s1 = "psyme" ascii wide nocase
$s2 = "js/psyme" ascii wide nocase
$s3 = "vbs/psyme" ascii wide nocase
$s4 = "trojandownloader:js/psyme" ascii wide nocase
$s5 = "win32/psyme" ascii wide nocase
condition:
uint16(0) == 0x5a4d and any of them
}Sigma Rule
title: Suspicious Psyme Activity
id: 4b780f00ec824b2628964a5541fa4fdf
status: experimental
description: Detects generic indicators of the psyme malware family.
logsource:
category: process_creation
product: windows
detection:
selection:
Image|endswith:
- '\cmd.exe'
- '\powershell.exe'
CommandLine|contains:
- "*psyme*"
- "*js/psyme*"
- "*vbs/psyme*"
- "*trojandownloader:js/psyme*"
- "*win32/psyme*"
condition: selection
level: mediumReferences & External Analysis
- Search "psyme" on VirusTotal (External Analysis)
Frequently Asked Questions
How do I remove the Psyme Ransomware from Windows?
Manual removal of Psyme 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 Psyme a virus or a Ransomware?
Psyme is classified as a Ransomware. Unlike traditional viruses that infect files, modern malware like Psyme typically operates as a standalone payload designed to compromise systems, steal data, or deploy secondary stage implants.
What are the main symptoms of a Psyme infection?
Symptoms of Psyme 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: ransomware)
Explore other malware families in the same category:
Protect Your Network Against Ransomwares
Want to prevent Psyme and similar threats from compromising your organization? Read our comprehensive defensive guide: Ransomware Protection Guide.
Machine-readable
Get this profile as JSON: https://jordanricky1604-ship-it.github.io/malware-families-catalog/api/psyme.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.