Prast

Overview

Executive Summary

Distribution and Technical Behavior

• Browser Hijacking: 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.
• Ad Injection and Desktop Overlays: 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.
• System Alteration: 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.

Risk Assessment

Mitigation and Removal Strategies

• Endpoint Scanning: 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.
• Browser Remediation: 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.
• Application Control: Enforce strict application whitelisting policies to prevent standard users from executing unapproved software installers that are the primary vector for this adware.

Known aliases

Threat reports may refer to this family under multiple names:

• Adware.Prast
• PUP.Prast
• BrowserModifier:Win32/Prast

MITRE ATT&CK Techniques

This family has been observed using the following ATT&CK techniques: T1566.002 T1176 T1112

Tactical Mitigations

Based on the techniques used by this family, consider the following defensive strategies:

• T1566.002: Inspect email links for known malicious domains and use link-rewriting services for time-of-click analysis.

Generated Detections (Boilerplate)

These YARA and Sigma rules are auto-generated based on the family name and aliases. They must be heavily tuned before deployment in a production environment.

YARA Rule

rule MALWARE_WIN_PRAST {
    meta:
        description = "Detects Prast (advanced_threat)"
        author = "SystemHelpdesk Boilerplate Generator"
        date = "2026-07-06"
    strings:
        $s1 = "prast" ascii wide nocase
        $s2 = "adware.prast" ascii wide nocase
        $s3 = "pup.prast" ascii wide nocase
        $s4 = "browsermodifier:win32/prast" ascii wide nocase
    condition:
        uint16(0) == 0x5a4d and any of them
}

Sigma Rule

title: Suspicious Prast Activity
id: fa12b4fb92f1cc6cbbf46d501b508d7f
status: experimental
description: Detects generic indicators of the prast malware family.
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        Image|endswith:
            - '\cmd.exe'
            - '\powershell.exe'
        CommandLine|contains:
            - "*prast*"
            - "*adware.prast*"
            - "*pup.prast*"
            - "*browsermodifier:win32/prast*"
    condition: selection
level: medium

References & External Analysis

• Search "prast" on VirusTotal (External Analysis)

Frequently Asked Questions

Related Families (Category: advanced_threat)

Explore other malware families in the same category:

• Alinaos
• Trymedia
• Slimdrivers
• Silentinstall
• Klez

Machine-readable

Get this profile as JSON: https://jordanricky1604-ship-it.github.io/malware-families-catalog/api/prast.json

Ecosystem & Interactive Environments

This profile is part of the Malware Families Catalog, a public dataset of 2,899 malware families. The catalog is also published across our ecosystem: Hugging Face, Kaggle, Zenodo, Replit, StackBlitz, CodeSandbox, and CodePen.