{
  "family": "staem",
  "sample_count": 1,
  "category": "trojan",
  "description": "<h3>Executive Summary</h3>\n\"Staem\" (a deliberate misspelling of \"Steam\") is a classification for a specific type of Phishing Trojan and Information Stealer designed to target users of the Valve Steam gaming platform. Its primary objective is the theft of Steam account credentials, bypassing Steam Guard (2FA), and ultimately stealing valuable in-game inventories (like CS:GO skins) and hijacking the account for resale.\n\n<h3>Infection Vector and Technical Capabilities</h3>\nStaem trojans are heavily distributed via social engineering within the Steam community itself. Attackers compromise one account, then message the victim's friends list with links to fake tournament sign-ups, \"free skin\" giveaways, or deceptive trading sites. The malware is often disguised as a VoIP client (like a fake TeamSpeak or Discord update) required to join a game.\n\nUpon execution, it performs a highly targeted data harvesting operation:\n<ul>\n<li><strong>Credential Phishing Overlays:</strong> The trojan often operates by detecting when the legitimate Steam client is launched. It then immediately suspends the legitimate process and overlays a pixel-perfect, fake Steam login window on top. When the user enters their username and password, it is captured by the malware.</li>\n<li><strong>Steam Guard Bypass (SSFN File Theft):</strong> To bypass Steam's two-factor authentication, the malware actively hunts for the hidden `ssfn*` files located in the Steam installation directory. These files act as persistent authorization tokens.</li>\n<li><strong>Data Exfiltration:</strong> The stolen credentials and the `ssfn` files are bundled and transmitted to the attacker's C2 server. The attacker can then use these files to log into the victim's account from a remote machine without triggering a Steam Guard code request.</li>\n</ul>\n\n<h3>Threat Assessment</h3>\nWhile a Staem infection primarily targets personal gaming assets rather than corporate financial data, it represents a significant security breach. The hijacked account is immediately used to spread the malware further. Furthermore, users frequently reuse passwords; a compromised gaming password could lead to the compromise of the user's primary email or banking accounts.\n\n<h3>Incident Response and Remediation</h3>\n<ul>\n<li><strong>Immediate Account Recovery:</strong> The victim must immediately attempt to recover their account via Steam Support, locking the account to prevent the trade of valuable inventory items.</li>\n<li><strong>Global Credential Reset:</strong> A complete password reset for the Steam account and ANY other service that shares the same password must be performed from a *different, clean device*.</li>\n<li><strong>Endpoint Eradication:</strong> Run a full system scan using a reputable enterprise antivirus solution to remove the Staem executable and any associated keylogging components.</li>\n</ul>",
  "cta": "Published by the SystemHelpdesk team.",
  "aliases": [
    "Trojan.SteamStealer",
    "PWS.Steam",
    "Phish.Staem"
  ],
  "enrichment_level": "insufficient_information",
  "faq": [],
  "faq_count": 0,
  "mitre_attack": [
    "T1555.003",
    "T1539",
    "T1056.002",
    "T1114"
  ],
  "cisa_advisory": null,
  "last_updated": "2026-07-02T06:54:00Z",
  "type": "Information Stealer / Phishing Trojan",
  "target_industries": [
    "Global / Opportunistic"
  ],
  "motivation": "Opportunistic",
  "threat_actors": [
    "Unknown / Cybercriminal"
  ],
  "target_geographies": [
    "Global"
  ]
}