{
  "family": "delphinjector",
  "sample_count": 1,
  "category": "ransomware",
  "description": "Trojan:Win32/Delphinjector is a generic classification for malware or specialized droppers written in Delphi whose primary function is Process Injection (`T1055`). Delphi is popular among threat actors (like the authors of Emotet or early Ryuk variants) because it compiles into large, complex, standalone executables that are difficult to analyze statically and often bypass basic AV heuristics.<br><br><b>Understanding Delphinjector</b><br>To an end-user, the execution is invisible. For a SOC analyst, a Delphinjector detection is a major red flag indicating that a highly evasive staging mechanism has breached the endpoint. The Delphi binary is almost certainly a 'wrapper' designed to hollow out a legitimate process and inject a more destructive payload (like Cobalt Strike or ransomware) into memory.<br><br><b>Execution and Injection Mechanics</b><br>Upon execution, the Delphi executable typically drops a highly obfuscated payload into memory. It then launches a legitimate, trusted Windows process (like `svchost.exe`, `explorer.exe`, or `RegAsm.exe`) in a suspended state (`T1055.012`). It unmaps (hollows) the legitimate code from the suspended process's memory and injects its own malicious code. Finally, it resumes the thread. To the OS and many EDR tools, the executing code appears to be the legitimate Microsoft binary, completely bypassing application whitelisting and firewall rules.<br><br><b>Indicators of Compromise & Impact</b><br>The impact depends on the injected payload. Host-based IoCs require behavioral analysis (EDR). Analysts should look for a Delphi-compiled executable spawning legitimate Windows binaries (like `svchost.exe`) without the appropriate command-line arguments. Network IoCs involve that 'legitimate' process suddenly making outbound connections to low-reputation IP addresses. Memory forensics (dumping the `svchost.exe` process) is strictly required to extract the actual payload.",
  "cta": "Published by the SystemHelpdesk team.",
  "aliases": [],
  "enrichment_level": "expert-seo",
  "faq": [
    {
      "@type": "Question",
      "name": "What is Delphinjector and what threat category does it belong to?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Delphinjector 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 Delphinjector establish persistence and evade defensive controls?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Delphinjector 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 Delphinjector compromise?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Security teams responding to Delphinjector 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 Delphinjector employ during execution?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Delphinjector 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 Delphinjector, and what is the recommended recovery procedure?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Decryption availability for Delphinjector 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": [
    "T1027",
    "T1055.012",
    "T1055"
  ],
  "cisa_advisory": null,
  "last_updated": "2026-06-09",
  "mitre_attack_detail": [
    {
      "id": "T1055",
      "name": "Process Injection (The core behavior of this family)",
      "tactic": "Defense Evasion"
    },
    {
      "id": "T1055.012",
      "name": "Process Injection: Process Hollowing (Specifically targeting legitimate binaries)",
      "tactic": "Defense Evasion"
    },
    {
      "id": "T1027",
      "name": "Obfuscated Files or Information (Using Delphi to complicate static analysis)",
      "tactic": "Defense Evasion"
    }
  ],
  "containment_steps": [
    "Isolate the endpoint immediately; process injection is a precursor to severe attacks like ransomware or lateral movement.",
    "Use EDR tools to identify the legitimate process that was hollowed out (e.g., `svchost.exe`) and terminate it.",
    "Capture a live RAM dump of the infected host to allow forensic analysts to extract the injected payload from memory.",
    "Investigate the initial execution of the Delphi executable (often a macro-enabled document or a downloaded crack)."
  ],
  "what_to_avoid": [
    "Do not assume the machine is clean just because the initial Delphinjector executable was quarantined; the payload may already be running in memory.",
    "Avoid whitelisting standard Windows binaries globally in your EDR, as this ignores process hollowing."
  ],
  "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,
  "target_platforms": [
    "Windows 11",
    "Windows 10",
    "Windows Server 2022",
    "Windows Server 2019"
  ]
}