Ryuk | Threat Level: critical | Type: Ransomware

Cryptographic Identifiers

SHA256327da452b8c86ed8910056646771de8fb92a928c3d135efb2d41e6cb26806382
MD542513d9fbd45e442f8f499a7bb5746a2
File Typeexe
Size7877.8 KB
First Seen2020-10-22
File NameReport-Review22-10.exe
TagsBazaLoader, Ransomware, Ryuk, ZLoader

Malware Family: Ryuk

Ryuk, hastane hedefler.

TypeRansomware
Programming LanguageC
Target PlatformWindows
C2 Protocol
PurposeHastane ransomware
First Seen Year2018

Threat Indicators (IOC)

  • SHA256: 327da452b8c86ed8910056646771de8fb92a928c3d135efb2d41e6cb26806382
  • MD5: 42513d9fbd45e442f8f499a7bb5746a2

You can verify all hash values of this sample on VirusTotal.

System Cleanup Guide

  1. Sistemi ağdan DERHAL ayırın — diğer cihazlara yayılmayı durdurun
  2. Do not pay the ransom — there is no guarantee your files will be restored
  3. Quarantine the affected drives
  4. Kullanılan fidye yazılımı ailesini belirleyin (nomoreransom.org)
  5. Try available decryptor tools (the NoMoreRansom project)
  6. Report the incident to the authorities (cybercrime unit)
  7. Temiz bir yedekten kurtarın; yedeğiniz yoksa sürücüyü saklayın

YARA Rule Hints

rule Ryuk_SHA256 {
    meta:
        description = "Ryuk sample: 327da452b8c86ed8"
        threat_level = "critical"
        first_seen = "2020-10-22"
    condition:
        hash.sha256(0, filesize) == "327da452b8c86ed8910056646771de8fb92a928c3d135efb2d41e6cb26806382"
}

Ryuk — Malware Profile

Wizard Spider threat group ransomware (2018+). Targets large enterprises, hospitals, municipalities. RyukReadMe.html ransom note. VirtualAllocEx+WriteProcessMemory+CreateRemoteThread injection. GetIpNetTable ARP scan for lateral movement. AdjustTokenPrivileges for SeBackupPrivilege/SeDebugPrivilege.

Malware Type
Ransomware
Programming Language
C
C2 Protocol
Target Systems
Windows

Technical Details

Ryuk ransomware emerged August 2018, operated by WIZARD SPIDER (TrickBot operators). Targeted large organizations for high ransoms ($100K-$12.5M+ per victim). Distribution: delivered via TrickBot/BazarLoader infections (human-operated). Encryption: RSA-2048 + AES-256 (CBC mode), unique key per file. Stops 40+ Windows services (backup, antivirus, database) and kills >180 processes. Deletes volume shadow copies (vssadmin delete shadows /all /Quiet). Disables Windows recovery: bcdedit /set {default} recoveryenabled No. Network propagation: uses Wake-on-LAN to activate sleeping network hosts for encryption. Believed based on Hermes ransomware sold by a North Korean-linked actor on underground forums. Predecessor to Conti ransomware which emerged from WIZARD SPIDER's operations in 2020.

Attribution / Threat Actor

WIZARD SPIDER (linked to Hermes/Lazarus initial code)

Capabilities & Behavior

Dosya Şifreleme (AES/RSA)
Gölge Kopya Silme
Yedek Kaldırma
Fidye Notu Oluşturma
Kalıcılık Sağlama
Ağ Paylaşımı Şifreleme
Anti-Analiz Teknikleri
Çift Gasp (Data Leak)

IOC List (2 indicators)

IOC — Ryuk
# SHA256 327da452b8c86ed8910056646771de8fb92a928c3d135efb2d41e6cb26806382 # MD5 42513d9fbd45e442f8f499a7bb5746a2
TypeValueNote
sha256 327da452b8c86ed8910056646771de8fb92a928c3d135efb2d41e6cb26806382 Sample:Ryuk
md5 42513d9fbd45e442f8f499a7bb5746a2 Sample:Ryuk

C2 Servers (2 recorded servers for this family)

Address Type Port Protocol Status Country
51.161.204.106 ip 443 HTTPS sinkholed CA
162.119.249.198 ip 443 HTTPS sinkholed US

C2 addresses are provided only from malware samples manually verified by the KEYDAL team. Commercial use is prohibited.

Tags
ryukransomwaremalwarecriticalsha256hash-analizi