Where can I learn more about gepys?

Refer to the linked MITRE ATT&CK technique pages, which document the behaviors associated with this family.

Gepys Malware Family: IOCs, Detection, MITRE ATT&CK, Response

Overview

Executive Summary

Gepys is a malicious Trojan designed to covertly infiltrate Windows systems, establish persistence, and act as a reliable downloader for remote threat actors. It is frequently utilized in the initial stages of a cyberattack to gather system intelligence and facilitate the automated deployment of secondary, highly destructive malware payloads, such as enterprise ransomware or banking trojans.

Infection Vector and Technical Capabilities

Gepys is predominantly distributed through socially engineered spam campaigns containing malicious attachments (often weaponized PDFs or Office documents utilizing macro exploits) or via compromised software installers downloaded from untrustworthy web portals. Upon successful execution, Gepys operates with a focus on stealth and payload delivery:

System Reconnaissance: The trojan immediately collects detailed system information, including the OS version, installed software, Active Directory domain membership, and active antivirus solutions. This fingerprint is transmitted to a command-and-control (C2) server.
Persistence: Gepys ensures it survives system reboots by modifying the Windows Registry (e.g., adding entries to the `Run` or `RunOnce` keys) or by creating hidden Scheduled Tasks that execute the malware payload under high privileges.
Payload Delivery: Acting as a downloader, Gepys receives instructions from the C2 server to silently download and execute secondary malware. This provides the attacker with a flexible platform to escalate the attack based on the value of the compromised host.

Threat Assessment

A Gepys infection represents a significant breach of the endpoint perimeter. Because it provides remote attackers with the ability to execute arbitrary code, a single compromised machine can rapidly be utilized to pivot laterally and compromise the entire corporate network.

Remediation and Eradication

Endpoint Detection and Response (EDR): Configure EDR solutions to monitor for anomalous registry modifications and unauthorized outbound network connections to unknown IP addresses.
Network Isolation and Sweeps: Immediately isolate the infected endpoint from the LAN. Conduct a thorough forensic sweep to identify not only the Gepys executable but also any secondary payloads it may have successfully deployed.
Credential Reset: Because Gepys frequently facilitates the deployment of info-stealers, all user credentials associated with the compromised endpoint must be treated as compromised and immediately reset.

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_GEPYS {
    meta:
        description = "Detects Gepys (trojan_generic)"
        author = "SystemHelpdesk Boilerplate Generator"
        date = "2026-07-06"
    strings:
        $s1 = "gepys" ascii wide nocase
        $s2 = "trojan.gepys" ascii wide nocase
        $s3 = "downloader.gepys" ascii wide nocase
        $s4 = "win32/gepys" ascii wide nocase
    condition:
        uint16(0) == 0x5a4d and any of them
}

Sigma Rule

title: Suspicious Gepys Activity
id: 8b02fe5fe2aab7f6d35d18c34b172a09
status: experimental
description: Detects generic indicators of the gepys malware family.
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        Image|endswith:
            - '\cmd.exe'
            - '\powershell.exe'
        CommandLine|contains:
            - "*gepys*"
            - "*trojan.gepys*"
            - "*downloader.gepys*"
            - "*win32/gepys*"
    condition: selection
level: medium

Gepys

Overview

Executive Summary

Infection Vector and Technical Capabilities

Threat Assessment

Remediation and Eradication

Known aliases

MITRE ATT&CK Techniques

Generated Detections (Boilerplate)

YARA Rule

Sigma Rule

References & External Analysis

Frequently Asked Questions

Related Families (Category: trojan_generic)

Machine-readable

Ecosystem & Interactive Environments