{
  "family": "prast",
  "sample_count": 1,
  "category": "advanced_threat",
  "description": "<h3>Executive Summary</h3>\nPrast is a pervasive family of Potentially Unwanted Programs (PUPs) and aggressive Adware. Masquerading as a convenient system utility, browser add-on, or \"free\" application, its true objective is to monetize the user's system by hijacking web traffic, altering browser configurations, and injecting highly intrusive, unclosable advertisements and sponsored content onto the desktop.\n\n<h3>Distribution and Technical Behavior</h3>\nPrast is heavily distributed via deceptive advertising networks and bundled within the \"Express Installation\" settings of free software downloaded from low-reputation download portals.\n\nOnce installed, Prast deeply integrates with the operating system and installed web browsers:\n<ul>\n<li><strong>Browser Hijacking:</strong> The PUP forcefully alters the browser's default search engine, homepage, and new tab settings. It redirects all search traffic through a specific portal controlled by the adware operators, allowing them to intercept queries and generate pay-per-click revenue.</li>\n<li><strong>Ad Injection and Desktop Overlays:</strong> The software acts as a desktop widget, constantly pulling dynamic, unverified advertisements from remote servers. It can also inject banners, pop-unders, and sponsored links directly into the user's web viewing experience.</li>\n<li><strong>System Alteration:</strong> To ensure it remains active, Prast creates persistent Scheduled Tasks and modifies the Windows Registry to automatically launch its ad-serving components upon system boot.</li>\n</ul>\n\n<h3>Risk Assessment</h3>\nWhile Prast is not a destructive virus (it does not encrypt files or steal banking credentials), it introduces massive operational friction and privacy risks. The continuous ad injections severely degrade system performance, and the hijacked search results are frequently served by low-tier ad networks, significantly increasing the risk of exposure to more severe \"malvertising\" attacks.\n\n<h3>Mitigation and Removal Strategies</h3>\n<ul>\n<li><strong>Endpoint Scanning:</strong> Utilize a reputable enterprise-grade anti-malware solution to perform a deep system scan, targeting the Prast executables, hidden scheduled tasks, and persistent registry keys.</li>\n<li><strong>Browser Remediation:</strong> Manually inspect and remove any unknown or unauthorized extensions from all installed web browsers. Perform a complete factory reset of the browsers to clear the hijacked proxy and search settings.</li>\n<li><strong>Application Control:</strong> Enforce strict application whitelisting policies to prevent standard users from executing unapproved software installers that are the primary vector for this adware.</li>\n</ul>",
  "cta": "Published by the SystemHelpdesk team.",
  "aliases": [
    "Adware.Prast",
    "PUP.Prast",
    "BrowserModifier:Win32/Prast"
  ],
  "enrichment_level": "expert-seo",
  "faq": [
    {
      "@type": "Question",
      "name": "What is Prast and what threat category does it belong to?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Prast is classified as a Advanced Threat. 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 Prast establish persistence and evade defensive controls?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Prast 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 Prast compromise?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Security teams responding to Prast 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 lateral movement and credential access tactics does Adware.Prast leverage in enterprise intrusions?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Adware.Prast frequently utilizes privileged account harvesting techniques such as LSASS memory dumping, Kerberoasting, and token impersonation to escalate privileges. Once administrative credentials are acquired, it pivots across the victim network utilizing living-off-the-land binaries (LOLBins) such as WMI, PowerShell remoting, and PsExec, or abuses remote desktop protocols (RDP) to reach critical internal repositories and domain controllers."
      }
    },
    {
      "@type": "Question",
      "name": "How does Adware.Prast maintain covert communications and evade perimeter network monitoring?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Adware.Prast often relies on multi-stage command and control (C2) architectures utilizing encrypted protocols over standard web ports (HTTPS/443 or DNS tunneling) to blend in with legitimate enterprise network traffic. Many variants incorporate proxy networks, domain fronting, or cloud services (such as Microsoft Graph API, Google Drive, or Telegram) to masquerade C2 channels, bypassing traditional signature-based egress filtering."
      }
    }
  ],
  "faq_count": 5,
  "mitre_attack": [
    "T1566.002",
    "T1176",
    "T1112"
  ],
  "cisa_advisory": null,
  "last_updated": "2026-10-15",
  "type": "Adware / PUP",
  "target_industries": [
    "Global / Opportunistic"
  ],
  "motivation": "Opportunistic",
  "threat_actors": [
    "Unknown / Cybercriminal"
  ],
  "target_geographies": [
    "Global"
  ],
  "attack_stage": [
    "execution",
    "persistence"
  ],
  "ecosystem": [
    "windows_pe"
  ],
  "is_emerging": false,
  "mitre_attack_detail": [
    {
      "id": "T1566.002",
      "name": "Phishing: Spearphishing Link (Social engineering to force the user to download the tool)",
      "tactic": "Initial Access"
    },
    {
      "id": "T1176",
      "name": "Browser Extensions",
      "tactic": "Persistence"
    },
    {
      "id": "T1112",
      "name": "Modify Registry",
      "tactic": "Defense Evasion"
    }
  ],
  "containment_steps": [
    "Enforce forensic network isolation on all suspected endpoints while maintaining an out-of-band telemetry conduit to capture live Prast adversary activity.",
    "Perform full memory dumps across identified staging nodes to extract memory-only implants, kernel rootkit hooks, and decrypted Prast C2 infrastructure IP/domain lists.",
    "Review Active Directory domain controller authentication logs for anomalous Kerberos ticket requests (Pass-the-Ticket, Golden Ticket) and unauthorized DCSync operations associated with Prast.",
    "Block all confirmed C2 domains, dynamic DNS endpoints, and proxy IP addresses across perimeter firewalls, proxies, and DNS security gateways.",
    "Conduct an enterprise-wide sweep across surrounding subnets for secondary webshells, WMI event subscriptions, or remote execution tooling left behind by Prast operators."
  ],
  "what_to_avoid": [
    "Do not assume the incident is resolved simply because an antivirus tool removed the initial Prast dropper; always verify that secondary payloads and persistence hooks have been eradicated.",
    "Avoid logging in with Domain Admin or privileged credentials on a machine suspected of running Prast until memory triage is complete.",
    "Do not delay host isolation; automated lateral movement and credential dumping can occur within minutes of initial execution."
  ],
  "target_platforms": [
    "Windows 11",
    "Windows 10",
    "Windows Server 2022",
    "Windows Server 2019"
  ]
}