{ "family": "rostpay", "sample_count": 1, "category": "ransomware", "description": "

Executive Summary

\nRostpay is a malicious Trojan that frequently exhibits destructive behavior, often operating as a \"locker\" ransomware or a data-wiping utility. Unlike sophisticated, enterprise-targeting ransomware (which uses strong cryptography to hold files hostage), Rostpay variants often simply lock the user's screen or scramble files in a crude, often irreversible manner to extort a small ransom or simply cause disruption.\n\n

Infection Vector and Technical Capabilities

\nRostpay is predominantly distributed through deceptive software downloads, fake cracks/keygens on untrustworthy websites, or via malspam campaigns targeting individuals rather than large enterprises.\n\nUpon successful execution, Rostpay initiates a disruptive attack sequence:\n\n\n

Threat Assessment

\nWhile a Rostpay infection might lack the sophistication of an APT or major ransomware gang, it represents a severe, immediate loss of system availability. The crude nature of the malware means that even if a ransom is paid, data recovery is often impossible because the files were corrupted rather than properly encrypted.\n\n

Incident Response and Remediation

\n", "cta": "Published by the SystemHelpdesk team.", "aliases": [ "Trojan.Rostpay", "Ransom.Locker.Rostpay", "Win32/Rostpay" ], "enrichment_level": "expert-seo", "faq": [ { "@type": "Question", "name": "What is Rostpay and what threat category does it belong to?", "acceptedAnswer": { "@type": "Answer", "text": "Rostpay is classified as a Ransomware. Documented across security telemetry, it is engineered to execute unauthorized operations, establish persistent footholds on target endpoints, and facilitate malicious campaigns targeting enterprise and individual environments." } }, { "@type": "Question", "name": "How does Rostpay establish persistence and evade defensive controls?", "acceptedAnswer": { "@type": "Answer", "text": "Rostpay typically establishes persistence through registry run keys, scheduled tasks, or service installations, while evading signature-based antivirus solutions through code obfuscation, memory injection, or anti-analysis sandbox checks." } }, { "@type": "Question", "name": "What are the essential incident response steps for mitigating a Rostpay compromise?", "acceptedAnswer": { "@type": "Answer", "text": "Security teams responding to Rostpay should immediately isolate affected endpoints from the network, perform memory triage to capture volatile forensic artifacts, audit registry and startup persistence mechanisms, revoke exposed user credentials, and restore systems from verified, clean backups." } }, { "@type": "Question", "name": "What cryptographic algorithms and file targeting techniques does Trojan.Rostpay employ during execution?", "acceptedAnswer": { "@type": "Answer", "text": "Trojan.Rostpay typically leverages hybrid cryptographic architectures combining symmetric stream or block ciphers (such as AES-256 or ChaCha20) for rapid file encryption with asymmetric algorithms (such as RSA-2048 or Curve25519) to securely protect the session keys. It aggressively targets sensitive file extensions including corporate documents, databases, virtual disks, and backups while systematically executing commands to delete Volume Shadow Copies (vssadmin delete shadows /all /quiet) and disable system recovery options." } }, { "@type": "Question", "name": "Are decryptors available for Trojan.Rostpay, and what is the recommended recovery procedure?", "acceptedAnswer": { "@type": "Answer", "text": "Decryption availability for Trojan.Rostpay depends on whether security researchers or law enforcement (such as the No More Ransom initiative) have recovered the master private keys or discovered flaws in its key generation routines. Victims should never pay the extortion demand, as payment fuels criminal operations without guaranteeing file restoration. The recommended recovery procedure entails isolating infected hosts, conducting forensic disk imaging, identifying the root access vector, and restoring validated systems from immutable offline backups." } } ], "faq_count": 5, "mitre_attack": [ "T1486", "T1491", "T1547.001" ], "cisa_advisory": null, "last_updated": "2026-10-15", "type": "Trojan / Ransomware (Locker)", "target_industries": [ "Healthcare", "Critical Infrastructure", "Enterprise" ], "motivation": "Financial Extortion", "threat_actors": [ "Unknown / Cybercriminal" ], "target_geographies": [ "Global" ], "attack_stage": [ "defense_evasion", "impact" ], "ecosystem": [ "windows_pe" ], "is_emerging": false, "mitre_attack_detail": [ { "id": "T1486", "name": "Data Encrypted for Impact", "tactic": "Impact" }, { "id": "T1491", "name": "Defacement (Displaying fake security warnings / Scareware)", "tactic": "Impact" }, { "id": "T1547.001", "name": "Boot or Logon Autostart Execution: Registry Run Keys / Startup Folder", "tactic": "Persistence" } ], "containment_steps": [ "Immediately isolate affected host(s) from the internal network (disconnect physical Ethernet and disable Wi-Fi/Bluetooth) to prevent Rostpay from spreading laterally or encrypting network-attached storage (NAS) and shared SMB volumes.", "Preserve volatile system memory (RAM capture) on a representative endpoint before attempting a reboot or power-down, as Rostpay symmetric encryption keys or uncompiled payload components may still reside in memory.", "Audit process execution logs and terminate active scripting interpreters (e.g. PowerShell, CMD, WScript) or commands executing 'vssadmin.exe delete shadows' or 'wbadmin' used by Rostpay to inhibit recovery.", "Investigate the initial compromise vector (such as exposed RDP instances, spearphishing attachments, or vulnerable edge gateways) and enforce an immediate credential reset for all compromised Active Directory accounts.", "Restore critical assets and databases exclusively from verified, air-gapped, or immutable offline backups once the Rostpay binary and related persistence hooks are eradicated." ], "what_to_avoid": [ "Do not restart or power cycle infected systems prematurely; doing so destroys volatile RAM encryption keys and may trigger bootloader locking logic embedded in Rostpay.", "Avoid negotiating or paying the extortion demand without prior forensic evaluation and consultation with incident response specialists, as payment does not guarantee data recovery.", "Do not connect clean backup drives or external storage to the affected network until Rostpay eradication is completely verified." ], "target_platforms": [ "Windows 11", "Windows 10", "Windows Server 2022", "Windows Server 2019" ] }