Potential Masquerading as Business App Installer

Last updated 9 days ago on 2025-05-05
Created 2 years ago on 2023-09-01

About

Identifies executables with names resembling legitimate business applications but lacking signatures from the original developer. Attackers may trick users into downloading malicious executables that masquerade as legitimate applications via malicious ads, forum posts, and tutorials, effectively gaining initial access.
Tags
Domain: EndpointData Source: Elastic DefendOS: WindowsUse Case: Threat DetectionTactic: Defense EvasionTactic: Initial AccessTactic: ExecutionLanguage: eql
Severity
low
Risk Score
21
MITRE ATT&CK™

Defense Evasion (TA0005)(opens in a new tab or window)

Initial Access (TA0001)(opens in a new tab or window)

Execution (TA0002)(opens in a new tab or window)

License
Elastic License v2(opens in a new tab or window)

Definition

Rule Type
Event Correlation Rule
Integration Pack
Prebuilt Security Detection Rules
Index Patterns
logs-endpoint.events.process-*
Related Integrations

endpoint(opens in a new tab or window)

Query
process where host.os.type == "windows" and
  event.type == "start" and process.executable : "?:\\Users\\*\\Downloads\\*" and
  not process.code_signature.status : ("errorCode_endpoint*", "errorUntrustedRoot", "errorChaining") and
  (
    /* Slack */
    (process.name : "*slack*.exe" and not
      (process.code_signature.subject_name in (
        "Slack Technologies, Inc.",
        "Slack Technologies, LLC"
       ) and process.code_signature.trusted == true)
    ) or

    /* WebEx */
    (process.name : "*webex*.exe" and not
      (process.code_signature.subject_name in ("Cisco WebEx LLC", "Cisco Systems, Inc.") and process.code_signature.trusted == true)
    ) or

    /* Teams */
    (process.name : "teams*.exe" and not
      (process.code_signature.subject_name == "Microsoft Corporation" and process.code_signature.trusted == true)
    ) or

    /* Discord */
    (process.name : "*discord*.exe" and not
      (process.code_signature.subject_name == "Discord Inc." and process.code_signature.trusted == true)
    ) or

    /* WhatsApp */
    (process.name : "*whatsapp*.exe" and not
      (process.code_signature.subject_name in (
        "WhatsApp LLC",
        "WhatsApp, Inc",
        "24803D75-212C-471A-BC57-9EF86AB91435"
       ) and process.code_signature.trusted == true)
    ) or

    /* Zoom */
    (process.name : ("*zoom*installer*.exe", "*zoom*setup*.exe", "zoom.exe")  and not
      (process.code_signature.subject_name == "Zoom Video Communications, Inc." and process.code_signature.trusted == true)
    ) or

    /* Outlook */
    (process.name : "*outlook*.exe" and not
      (
        (process.code_signature.subject_name == "Microsoft Corporation" and process.code_signature.trusted == true) or
        (
          process.name: "MSOutlookHelp-PST-Viewer.exe" and process.code_signature.subject_name == "Aryson Technologies Pvt. Ltd" and
          process.code_signature.trusted == true
        )
      )
    ) or

    /* Thunderbird */
    (process.name : "*thunderbird*.exe" and not
      (process.code_signature.subject_name == "Mozilla Corporation" and process.code_signature.trusted == true)
    ) or

    /* Grammarly */
    (process.name : "*grammarly*.exe" and not
      (process.code_signature.subject_name == "Grammarly, Inc." and process.code_signature.trusted == true)
    ) or

    /* Dropbox */
    (process.name : "*dropbox*.exe" and not
      (process.code_signature.subject_name == "Dropbox, Inc" and process.code_signature.trusted == true)
    ) or

    /* Tableau */
    (process.name : "*tableau*.exe" and not
      (process.code_signature.subject_name == "Tableau Software LLC" and process.code_signature.trusted == true)
    ) or

    /* Google Drive */
    (process.name : "*googledrive*.exe" and not
      (process.code_signature.subject_name == "Google LLC" and process.code_signature.trusted == true)
    ) or

    /* MSOffice */
    (process.name : "*office*setup*.exe" and not
      (process.code_signature.subject_name == "Microsoft Corporation" and process.code_signature.trusted == true)
    ) or

    /* Okta */
    (process.name : "*okta*.exe" and not
      (process.code_signature.subject_name == "Okta, Inc." and process.code_signature.trusted == true)
    ) or

    /* OneDrive */
    (process.name : "*onedrive*.exe" and not
      (process.code_signature.subject_name == "Microsoft Corporation" and process.code_signature.trusted == true)
    ) or

    /* Chrome */
    (process.name : "*chrome*.exe" and not
      (process.code_signature.subject_name in ("Google LLC", "Google Inc") and process.code_signature.trusted == true)
    ) or

    /* Firefox */
    (process.name : "*firefox*.exe" and not
      (process.code_signature.subject_name == "Mozilla Corporation" and process.code_signature.trusted == true)
    ) or

    /* Edge */
    (process.name : ("*microsoftedge*.exe", "*msedge*.exe") and not
      (process.code_signature.subject_name == "Microsoft Corporation" and process.code_signature.trusted == true)
    ) or

    /* Brave */
    (process.name : "*brave*.exe" and not
      (process.code_signature.subject_name == "Brave Software, Inc." and process.code_signature.trusted == true)
    ) or

    /* GoogleCloud Related Tools */
    (process.name : "*GoogleCloud*.exe" and not
      (process.code_signature.subject_name == "Google LLC" and process.code_signature.trusted == true)
    ) or

    /* Github Related Tools */
    (process.name : "*github*.exe" and not
      (process.code_signature.subject_name == "GitHub, Inc." and process.code_signature.trusted == true)
    ) or

    /* Notion */
    (process.name : "*notion*.exe" and not
      (process.code_signature.subject_name == "Notion Labs, Inc." and process.code_signature.trusted == true)
    )
  )

Install detection rules in Elastic Security

Detect Potential Masquerading as Business App Installer in the Elastic Security detection engine by installing this rule into your Elastic Stack.

To setup this rule, check out the installation guide for Prebuilt Security Detection Rules(opens in a new tab or window).