{
  "family": "usteal",
  "sample_count": 28,
  "category": "trojan",
  "description": "TrojanSpy:Win32/Usteal is a dedicated credential stealing trojan engineered to silently harvest sensitive information from infected endpoints. It specifically targets saved passwords, session cookies, cryptocurrency wallets, and autocomplete data stored within web browsers and FTP clients.<br><br><b>Understanding Usteal</b><br>To the victim, Usteal operates completely invisibly. The computer continues to function normally while the malware systematically plunders its digital vaults. For threat intelligence analysts, Usteal is an 'Initial Access' facilitator. The data it steals is typically bundled into a ZIP archive and sold on Dark Web marketplaces like Genesis Market or Russian Market, providing other cybercriminals with the credentials needed to breach corporate VPNs or drain bank accounts.<br><br><b>Execution and Exfiltration Strategies</b><br>Usteal is commonly distributed via phishing emails disguised as invoices or shipping documents, or bundled with cracked software. Upon execution, it does not typically attempt complex persistence or process hollowing. Its goal is a smash-and-grab operation. It queries the SQLite databases of popular browsers (Chrome, Firefox, Edge) to extract the `Login Data` and `Cookies` files (`T1555.003`). It searches for cryptocurrency wallet files (e.g., `wallet.dat`) (`T1552.004`). Once the data is collected, it is compressed, often encrypted, and exfiltrated to a C2 server via HTTP POST requests or Telegram bots (`T1048`).<br><br><b>Indicators of Compromise & Impact</b><br>The impact is severe credential compromise, leading directly to data breaches or financial theft. EDR platforms should alert on suspicious processes reading sensitive browser database files or attempting to access FTP client configurations. Network logs will reveal anomalous HTTP POST traffic containing large archives immediately following the execution of an untrusted file.",
  "cta": "Published by the SystemHelpdesk team.",
  "aliases": [],
  "enrichment_level": "expert-seo",
  "faq": [],
  "faq_count": 0,
  "mitre_attack": [
    "T1555.003",
    "T1056.001",
    "T1114.001",
    "T1048",
    "T1552.001"
  ],
  "cisa_advisory": null,
  "last_updated": "2026-06-09",
  "mitre_attack_detail": [
    {
      "id": "T1555.003",
      "name": "Credentials from Password Stores: Credentials from Web Browsers",
      "tactic": "Credential Access"
    },
    {
      "id": "T1552.001",
      "name": "Unsecured Credentials: Credentials In Files",
      "tactic": "Credential Access"
    },
    {
      "id": "T1048",
      "name": "Exfiltration Over Alternative Protocol",
      "tactic": "Exfiltration"
    },
    {
      "id": "T1114.001",
      "name": "Email Collection: Local Email Collection",
      "tactic": "Collection"
    },
    {
      "id": "T1056.001",
      "name": "Input Capture: Keylogging",
      "tactic": "Credential Access"
    }
  ],
  "containment_steps": [
    "Instantly isolate the endpoint from the network to halt the exfiltration of the stolen credential archives.",
    "Assume all passwords saved on the infected machine (browsers, FTP clients, VPNs) are compromised; initiate immediate, mandatory password resets.",
    "Invalidate all active session cookies for critical web applications (SSO portals, O365, AWS) to prevent session hijacking.",
    "Audit firewall logs for the destination IP addresses that Usteal contacted and block them enterprise-wide."
  ],
  "what_to_avoid": [
    "Do not assume the threat is over once the Usteal executable is deleted; the stolen credentials have already been exfiltrated and will be used.",
    "Avoid delaying password resets. The time between exfiltration and exploitation by a secondary threat actor can be a matter of hours."
  ],
  "target_industries": [
    "Global / Opportunistic"
  ],
  "motivation": "Opportunistic",
  "threat_actors": [
    "Unknown / Cybercriminal"
  ],
  "target_geographies": [
    "Global"
  ]
}