{ "family": "simda", "sample_count": 8, "category": "botnet", "description": "Simda is a versatile, highly evasive modular botnet and credential-theft trojan first detected in 2009. Engineered with aggressive anti-analysis routines, sandbox-detection algorithms, and server-side polymorphism, Simda was operated as a commercial pay-per-install (PPI) infrastructure, renting out compromised computers to secondary cybercriminals to distribute banking trojans, cryptocurrency miners, and search-hijacking adware.\n\nAt its peak, the Simda botnet enslaved an estimated 770,000 computers worldwide. In April 2015, the INTERPOL Global Complex for Innovation (IGCI) in Singapore coordinated 'Operation Simda'—a landmark international law enforcement strike in conjunction with the FBI, the Dutch National High Tech Crime Unit (NHTCU), the Police Grand-Ducale of Luxembourg, Russian Ministry of Internal Affairs (Department 'K'), Microsoft's Digital Crimes Unit, Kaspersky Lab, and Trend Micro. The operation seized 14 central command servers across the Netherlands, the United States, Luxembourg, Russia, and Poland, severing the operators' control and effectively dismantling the botnet. Kaspersky subsequently deployed a public IP-lookup portal allowing victims worldwide to check for infections.", "cta": "Published by the SystemHelpdesk team.", "aliases": [ "Simda", "Win32/Simda", "Trojan.Simda", "Backdoor.Simda" ], "enrichment_level": "curated_sourced", "faq": [ { "@type": "Question", "name": "What was the Simda botnet?", "acceptedAnswer": { "@type": "Answer", "text": "Simda was a large-scale commercial botnet that infected over 770,000 computers globally to steal passwords, commit ad click fraud, and distribute secondary malware." } }, { "@type": "Question", "name": "How was Simda dismantled?", "acceptedAnswer": { "@type": "Answer", "text": "In April 2015, an INTERPOL-led coalition including the FBI, Dutch police, Microsoft, and Kaspersky seized 14 command servers across five countries, severing bot communication." } }, { "@type": "Question", "name": "What vulnerabilities did Simda exploit for infection?", "acceptedAnswer": { "@type": "Answer", "text": "Simda was delivered via drive-by downloads using exploit kits targeting Microsoft XML Core Services (CVE-2012-1889) and Silverlight (CVE-2013-0074)." } }, { "@type": "Question", "name": "How did Simda prevent removal by antivirus tools?", "acceptedAnswer": { "@type": "Answer", "text": "Simda altered the Windows hosts file to block victim computers from accessing security update domains and terminated security processes via rootkit routines." } }, { "@type": "Question", "name": "How did victims check if they were infected with Simda?", "acceptedAnswer": { "@type": "Answer", "text": "Kaspersky Lab launched a free public portal where users could enter their IP address to see if it appeared in the seized Simda botnet database." } } ], "faq_count": 5, "mitre_attack": [ "T1055", "T1056.001", "T1562.001", "T1071.001", "T1568.002", "T1082" ], "cisa_advisory": null, "last_updated": "2026-06-09", "mitre_attack_detail": [ { "id": "T1562.002", "name": "Impair Defenses: Disable Windows Event Logging (Hosts file modification for traffic redirection)", "tactic": "Defense Evasion" }, { "id": "T1543.003", "name": "Create or Modify System Process: Windows Service", "tactic": "Persistence" }, { "id": "T1105", "name": "Ingress Tool Transfer (Acting as a PPI loader for other malware)", "tactic": "Command and Control" }, { "id": "T1189", "name": "Drive-by Compromise (Exploit Kits)", "tactic": "Initial Access" } ], "containment_steps": [ "Isolate the endpoint immediately; Simda acts as a loader, and secondary payloads (like banking trojans) are highly likely to be active.", "Manually inspect and clean the `%SystemRoot%\\System32\\drivers\\etc\\hosts` file, removing any unauthorized entries.", "Use a specialized, enterprise-grade rootkit removal tool or EDR to locate and terminate the hidden Simda services, as standard antivirus may fail to see them.", "Given the rootkit capabilities and the likelihood of secondary payload deployment, a complete rebuild of the operating system is highly recommended." ], "what_to_avoid": [ "Do not rely solely on automated remediation to fix the `hosts` file; verify the cleanup manually to ensure web traffic is no longer being intercepted.", "Avoid closing the incident after removing the initial Simda dropper; you must investigate what secondary payloads it may have downloaded." ], "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, "first_seen": 2009, "lineage": { "derived_from": [], "variants": [ "simda.a (2009)", "simda.b", "simda.c (server-side polymorphism)", "simda ppi loader" ] }, "attribution": [ { "actor": "Simda Cybercrime Syndicate / INTERPOL Operation Simda Coalition", "confidence": "high", "basis": "In April 2015, INTERPOL, the FBI, Dutch Police, and Russian authorities executed Operation Simda, seizing 14 central command servers across 5 nations to dismantle the 770,000-host botnet.", "source": "https://www.interpol.int/en/News-and-Events/News/2015/INTERPOL-coordinates-global-operation-to-take-down-Simda-botnet" } ], "exploited_cves": [ "CVE-2012-1889", "CVE-2013-0074", "CVE-2015-0071" ], "c2_profile": { "protocols": [ "HTTP", "HTTPS", "Encrypted Binary Protocol", "DGA Fallback" ], "ports": [ 80, 443, 8080 ], "infrastructure": "Fast-flux domain architecture with automated daily domain generation algorithms (DGA) querying hundreds of domains across .com, .net, and .info; seized during the April 2015 INTERPOL coordinated strike." }, "iocs": { "file_hashes": [ "4a242f36f6d895f462ebc8375e87a26f8303f26cfb16954316d2ca0190abf0c1", "e236526eb8fb386f6f1c4e97669e4f5530ecdfce9a2ffb38ab8fa176df2c75a4" ], "delivery": [ "Drive-by downloads from compromised websites hosting exploit kits targeting browser and Silverlight vulnerabilities (CVE-2013-0074)", "Malvertising campaigns redirecting traffic through stealthy iframe chains" ], "persistence": [ "Modifies Windows hosts file to block antivirus signature updates", "Registry Run keys and scheduled tasks executing injected DLLs in %APPDATA%" ] }, "sources": [ { "name": "INTERPOL Press Release - Global Operation Takes Down Simda Botnet", "url": "https://www.interpol.int/en/News-and-Events/News/2015/INTERPOL-coordinates-global-operation-to-take-down-Simda-botnet" }, { "name": "FBI National Press Release - Simda Botnet Disruption", "url": "https://www.fbi.gov/" }, { "name": "MITRE ATT&CK - Simda", "url": "https://attack.mitre.org/" } ], "target_platforms": [ "Windows 11", "Windows 10", "Windows 7" ] }