{
  "family": "berbew",
  "sample_count": 407,
  "category": "infostealer",
  "description": "Trojan:Win32/Berbew is a classic, highly persistent trojan downloader and backdoor known for establishing deep system hooks to steal credentials and download secondary malware.<br><br><b>What is Berbew?</b><br>For general users, Berbew often operates silently, though it may cause significant system instability. For security analysts, Berbew represents an older, but highly effective, class of trojan. It is specifically engineered to steal passwords from various applications (including browsers, FTP clients, and email clients) and act as a reliable conduit for attackers to push further updates or entirely new malware families onto the infected host.<br><br><b>Infection Vectors & Threat Hunting</b><br>Berbew is distributed via malicious email attachments, exploit kits, or bundled with pirated software. Upon execution, it drops its core executable into the <code>%SystemRoot%\\System32</code> directory. It achieves high-level persistence by injecting its code into <code>explorer.exe</code> or other critical system processes. It heavily modifies the Windows Registry (specifically the <code>Run</code>, <code>RunServices</code>, and <code>Browser Helper Object</code> keys) to ensure it executes silently in the background. Threat hunters should monitor for outbound TCP connections to hardcoded C2 IP addresses, often transmitting stolen credentials in lightly obfuscated formats.<br><br><b>Forensic Analysis & Impact</b><br>The impact of Berbew is a complete loss of credential security and an expanded attack surface due to the secondary payloads it downloads. Incident responders should analyze the registry for unauthorized BHOs (Browser Helper Objects) or Run keys pointing to anomalous executables in the System32 directory. Memory forensics is necessary to identify the specific processes that Berbew has injected its data-harvesting modules into.",
  "cta": "Published by the SystemHelpdesk team.",
  "aliases": [],
  "enrichment_level": "expert-seo",
  "faq": [],
  "faq_count": 0,
  "mitre_attack": [
    "T1055",
    "T1555",
    "T1176",
    "T1105",
    "T1547.001"
  ],
  "cisa_advisory": null,
  "last_updated": "2026-06-09",
  "mitre_attack_detail": [
    {
      "id": "T1055",
      "name": "Process Injection",
      "tactic": "Defense Evasion"
    },
    {
      "id": "T1555",
      "name": "Credentials from Password Stores",
      "tactic": "Credential Access"
    },
    {
      "id": "T1105",
      "name": "Ingress Tool Transfer",
      "tactic": "Command and Control"
    },
    {
      "id": "T1547.001",
      "name": "Boot or Logon Autostart Execution: Registry Run Keys / Startup Folder",
      "tactic": "Persistence"
    },
    {
      "id": "T1176",
      "name": "Browser Extensions",
      "tactic": "Persistence"
    }
  ],
  "containment_steps": [
    "Isolate the endpoint to halt the active exfiltration of stolen credentials and prevent the download of secondary malware.",
    "Force a password reset for all user accounts, as Berbew actively harvests credentials from multiple applications.",
    "Utilize EDR or memory forensics to locate and terminate the data-harvesting modules injected into <code>explorer.exe</code> or the web browsers.",
    "Audit the Windows Registry and meticulously remove the unauthorized BHOs and Run keys established by the trojan."
  ],
  "what_to_avoid": [
    "Do not allow the user to continue working on the infected machine, as the active keylogger/stealer captures all input.",
    "Avoid relying solely on manual file deletion in System32, as the injected processes will often recreate the dropped binaries."
  ],
  "target_industries": [
    "Financial Services",
    "Retail",
    "Consumers"
  ],
  "motivation": "Opportunistic",
  "threat_actors": [
    "Unknown / Cybercriminal"
  ],
  "target_geographies": [
    "Global"
  ]
}