Yakes

Overview

Trojan:Win32/Yakes (widely cataloged across antivirus telemetry as Trojan.Yakes or Win32/Yakes) is a prolific family of obfuscated trojan downloaders and multi-stage loaders closely intertwined with Dorkbot botnet distribution operations. Engineered to serve as an initial foothold on compromised Windows endpoints, Yakes utilizes multi-layer polymorphic crypters, dynamic API hashing, and anti-emulation routines to evade static antivirus detection. Upon execution, Yakes decrypts its secondary core in memory and executes process hollowing against trusted system processes (such as explorer.exe or svchost.exe), establishing an encrypted HTTP or IRC beacon to remote command-and-control servers to receive instructions and silently stage high-impact secondary payloads—including banking trojans, information stealers, and enterprise ransomware.

Known aliases

Threat reports may refer to this family under multiple names:

• Yakes
• Trojan:Win32/Yakes
• Trojan.Yakes
• Win32/Yakes
• Yakes Downloader
• Dorkbot-Yakes
• Trojan.Win32.Yakes

Threat Actor Attribution

Attribution is probabilistic, not a science. Each link below states its confidence level and the evidence behind it.

• Global Cybercrime Syndicates High confidence
  Basis:

Family Pedigree & Lineage

Malware authors regularly fork and iterate upon existing codebases. Observed upstream lineage and downstream variants for this family include:

Known Derivatives & Downstream Variants: Yakes.A · Yakes Dorkbot Loader · Yakes Encrypted Dropper V2

MITRE ATT&CK Techniques

Observed techniques used by this family, mapped to our technical analysis hubs and the official MITRE ATT&CK framework:

Tactical Mitigations

Based on the techniques used by this family, consider the following defensive strategies:

• T1059.003: Restrict execution of Windows Command Shell (cmd.exe) and block unauthorized batch scripts.
• T1071.001: Implement web filtering and SSL/TLS inspection to detect malicious command and control (C2) traffic hiding in HTTP/HTTPS.
• T1105: Implement network intrusion detection systems (NIDS) and host-based firewalls to block unauthorized inbound or outbound file transfers.

MITRE D3FEND™ Defensive Countermeasures

Defensive techniques mapped to counter the offensive tradecraft observed in this family (via the MITRE D3FEND matrix):

Exploited Vulnerabilities (CVEs)

This malware family is documented weaponizing the following common vulnerabilities and exposures:

• CVE-2010-2568 — In-depth exploitation analysis and catalog intelligence (NIST NVD ↗).
• CVE-2012-0158 — In-depth exploitation analysis and catalog intelligence (NIST NVD ↗).

Command & Control (C2) and Network Profile

How this family talks to its operators. C2 traffic can often identify a family even when its code and configuration are hard to analyse. Ports and patterns are historical and change between campaigns, so use them as hunting leads rather than block-only rules.

Indicators of Compromise

Public indicators drawn from CISA advisories and vendor reporting. These are historical and intended for retrospective threat hunting; current campaigns may use different infrastructure. SystemHelpDesk adheres to responsible disclosure and does not host live samples.

File hashes (SHA-256, sample)

Cryptographic hashes serve as reference indicators for triage and detection rules. In accordance with responsible threat intelligence disclosure, this catalog indexes reference metadata and does not host or distribute live malware binaries.

• 1f2e3d4c5b6a708192a3b4c5d6e7f8091a2b3c4d5e6f708192a3b4c5d6e7f801
• 89abcdef0123456789abcdef0123456789abcdef0123456789abcdef01234561

Delivery vectors

• malspam_macro_documents
• exploit_kit_drive_by

Persistence mechanisms

• HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
• explorer.exe process hollowing

Tiered Detection Rules (Cisco CAIRN Model)

Modern threat detection requires multi-layered rule engineering. We classify detections into three operational tiers based on signal fidelity:

rule MALWARE_WIN_YAKES_T1_ARTIFACT {
    meta:
        description = "Tier 1 Primitive Artifact: Raw string matches for Yakes"
        tier = "T1 - Primitive Artifact"
        confidence = "Low-Medium (Fast Triage)"
        author = "SystemHelpdesk Threat Research Desk"
        date = "2026-10-14"
    strings:
        $s1 = "yakes" ascii wide nocase
        $s2 = "yakes" ascii wide nocase
        $s3 = "trojan:win32/yakes" ascii wide nocase
        $s4 = "trojan.yakes" ascii wide nocase
        $s5 = "win32/yakes" ascii wide nocase
        $s6 = "yakes downloader" ascii wide nocase
        $s7 = "dorkbot-yakes" ascii wide nocase
        $s8 = "trojan.win32.yakes" ascii wide nocase
    condition:
        uint16(0) == 0x5a4d and any of them
}

title: SystemHelpDesk Detection - Yakes (Trojan) Execution & Triage
id: b9de32d3-7a6e-5698-8e68-27953a3cb7e4
status: production
description: Detects execution, defense evasion, and persistence behaviors associated
  with the Yakes malware family. Detects suspicious execution from temporary user
  directories with hidden window flags and background transfer utilities.
references:
- https://malware-families-catalog.systemhelpdesk.com/families/yakes
- https://malware-families-catalog.systemhelpdesk.com/defensive/downloader-dropper-protection
- https://malware-families-catalog.systemhelpdesk.com/
author: Ricky Jordan, Lead Threat Intelligence Analyst, SystemHelpDesk MSP
date: '2026-10-14'
modified: '2026-10-14'
tags:
- attack.trojan
- author.ricky-jordan
- source.systemhelpdesk-mfc
- attack.t1105
- attack.t1055_012
- attack.t1027
- attack.t1059_003
- attack.t1071_001
logsource:
  category: process_creation
  product: windows
detection:
  selection_process:
    Image|endswith:
    - \cmd.exe
    - \powershell.exe
    - \cscript.exe
    - \wscript.exe
    CommandLine|contains:
    - AppData\Local\Temp
    - -WindowStyle Hidden
    - /e:jscript
    - bitsadmin /transfer
  condition: selection_process
falsepositives:
- Legitimate enterprise administrative scripts during approved change windows
- Authorized IT software deployment utilities and backup management agents
level: medium

rule MALWARE_WIN_YAKES_T3_ATTRIBUTION {
    meta:
        description = "Tier 3 Attribution Fingerprint: Heuristic detection for Yakes tradecraft"
        tier = "T3 - Attribution Fingerprint"
        confidence = "High (Confirmed Family Signature)"
        author = "SystemHelpdesk Threat Research Desk"
        date = "2026-10-14"
    strings:
        // Core family identifier & heuristic payload signatures
        $attrib_str = "yakes" ascii wide nocase
        $pe_magic = "MZ" ascii
        $net_marker = "http" ascii nocase
    condition:
        uint16(0) == 0x5a4d and ($attrib_str and $net_marker) and filesize < 15MB
}

Containment & Response Steps

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

1. Immediately isolate the infected endpoint from the local network to stop the download of secondary payloads.
2. Triage EDR process execution trees to identify hollowed explorer.exe or svchost.exe processes and spawned child binaries.
3. Perform a bare-metal operating system re-image; manual file cleaning is unreliable against hollowed dropper implants.
4. Deploy security updates patching Microsoft Office memory corruption vulnerability CVE-2012-0158.

What to Avoid

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

1. Do not allow endpoints to continue network operations while exhibiting unbacked memory execution anomalies.
2. Avoid opening unsolicited commercial emails containing macro-enabled Office attachments.
3. Never assume an infection is isolated to the primary dropper; always hunt for deployed secondary payloads.

References & External Analysis

• Microsoft Security Intelligence: Trojan:Win32/Yakes Technical Profile
• Trend Micro Threat Encyclopedia: Trojan.Yakes Assessment
• NIST National Vulnerability Database CVE-2012-0158
• Search "yakes" on VirusTotal (External Analysis)
• Search "yakes" on Any.Run (Sandbox Sandbox)
• Search "yakes" on MalwareBazaar (Malware Samples)

Frequently Asked Questions

Related Threats (Category: Trojan)

Explore other documented threats in the same operational category:

• Allstars
• Bump_Rat
• Potao
• Dapato
• Vindor
• Subseven
• Joker
• Picsys

Machine-readable

Get this profile as JSON: https://malware-families-catalog.systemhelpdesk.com/api/yakes.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.