IMPORTANT: No additional bug fixes or documentation updates will be released for this version. For the latest information, see the current release documentation.

« Potential Local NTLM Relay via HTTP Potential Masquerading as Business App Installer »

› › ›

Potential Masquerading as Browser Process

edit

Potential Masquerading as Browser Process

edit

Identifies suspicious instances of browser processes, such as unsigned or signed with unusual certificates, that can indicate an attempt to conceal malicious activity, bypass security features such as allowlists, or trick users into executing malware.

Rule type: eql

Rule indices:

logs-endpoint.events.process-*

Severity: low

Risk score: 21

Runs every: 5m

Searches indices from: now-9m (Date Math format, see also Additional look-back time)

Maximum alerts per execution: 100

References: None

Tags:

Domain: Endpoint
OS: Windows
Use Case: Threat Detection
Tactic: Defense Evasion
Tactic: Persistence
Rule Type: BBR
Data Source: Elastic Defend

Version: 5

Rule authors:

Elastic

Rule license: Elastic License v2

Rule query

edit

process where host.os.type == "windows" and event.type == "start" and
  (
    /* Chrome Related Processes */
    (process.name : (
      "chrome.exe", "GoogleUpdate.exe", "GoogleCrashHandler64.exe", "GoogleCrashHandler.exe",
      "GoogleUpdateComRegisterShell64.exe", "GoogleUpdateSetup.exe", "GoogleUpdateOnDemand.exe",
      "chrome_proxy.exe", "remote_assistance_host.exe", "remoting_native_messaging_host.exe",
      "GoogleUpdateBroker.exe"
     ) and not
      (process.code_signature.subject_name : ("Google LLC", "Google Inc") and process.code_signature.trusted == true)
     and not
      (
        process.executable : (
          "?:\\Program Files\\HP\\Sure Click\\servers\\chrome.exe",
          "?:\\Program Files\\HP\\Sure Click\\*\\servers\\chrome.exe"
        ) and
        process.code_signature.subject_name : ("Bromium, Inc.") and process.code_signature.trusted == true
      ) and not
      (
        process.executable : (
          "?:\\Program Files\\dynatrace\\synthetic\\Chrome-bin\\chrome.exe"
        ) and
        process.code_signature.subject_name : ("Dynatrace LLC") and process.code_signature.trusted == true
      ) and
     not (
       process.executable : (
         "?:\\Users\\*\\AppData\\Local\\ms-playwright\\chromium-*\\chrome-win\\chrome.exe",
         "?:\\Users\\*\\AppData\\Local\\Programs\\synthetics-recorder\\resources\\local-browsers\\chromium-*\\chrome-win\\chrome.exe",
         "*\\node_modules\\puppeteer\\.local-chromium\\win64-*\\chrome-win\\chrome.exe",
         "?:\\Program Files (x86)\\Invicti Professional Edition\\chromium\\chrome.exe",
         "?:\\Program Files\\End2End, Inc\\ARMS Html Engine\\chrome.exe",
         "?:\\Users\\*\\AppData\\Local\\*BurpSuitePro\\burpbrowser\\*\\chrome.exe",
         "?:\\Users\\*\\AppData\\Roaming\\*BurpSuite\\burpbrowser\\*\\chrome.exe"
       ) and process.args: (
               "--enable-features=NetworkService,NetworkServiceInProcess",
               "--type=crashpad-handler", "--enable-automation", "--disable-xss-auditor"
             )
     )
    ) or

    /* MS Edge Related Processes */
    (process.name : (
      "msedge.exe", "MicrosoftEdgeUpdate.exe", "identity_helper.exe", "msedgewebview2.exe",
      "MicrosoftEdgeWebview2Setup.exe", "MicrosoftEdge_X*.exe", "msedge_proxy.exe",
      "MicrosoftEdgeUpdateCore.exe", "MicrosoftEdgeUpdateBroker.exe", "MicrosoftEdgeUpdateSetup_X*.exe",
      "MicrosoftEdgeUpdateComRegisterShell64.exe", "msedgerecovery.exe", "MicrosoftEdgeUpdateSetup.exe"
     ) and not
      (process.code_signature.subject_name : "Microsoft Corporation" and process.code_signature.trusted == true)
     and not
      (
        process.name : "msedgewebview2.exe" and
        process.code_signature.subject_name : ("Bromium, Inc.", "Amazon.com Services LLC", "Code Systems Corporation") and process.code_signature.trusted == true
      )
    ) or

    /* Brave Related Processes */
    (process.name : (
      "brave.exe", "BraveUpdate.exe", "BraveCrashHandler64.exe", "BraveCrashHandler.exe",
      "BraveUpdateOnDemand.exe", "brave_vpn_helper.exe", "BraveUpdateSetup*.exe",
      "BraveUpdateComRegisterShell64.exe"
     ) and not
      (process.code_signature.subject_name : "Brave Software, Inc." and process.code_signature.trusted == true)
    ) or

    /* Firefox Related Processes */
    (process.name : (
      "firefox.exe", "pingsender.exe", "default-browser-agent.exe", "maintenanceservice.exe",
      "plugin-container.exe", "maintenanceservice_tmp.exe", "maintenanceservice_installer.exe",
      "minidump-analyzer.exe"
     ) and not
      (process.code_signature.subject_name : "Mozilla Corporation" and process.code_signature.trusted == true)
     and not
      (
        process.name : "default-browser-agent.exe" and
        process.code_signature.subject_name : ("WATERFOX LIMITED") and process.code_signature.trusted == true
      )
    ) or

    /* Island Related Processes */
    (process.name : (
      "Island.exe", "IslandUpdate.exe", "IslandCrashHandler.exe", "IslandCrashHandler64.exe",
      "IslandUpdateBroker.exe", "IslandUpdateOnDemand.exe", "IslandUpdateComRegisterShell64.exe",
      "IslandUpdateSetup.exe"
     ) and not
      (process.code_signature.subject_name : "Island Technology Inc." and process.code_signature.trusted == true)
    ) or

    /* Opera Related Processes */
    (process.name : (
      "opera.exe", "opera_*.exe", "browser_assistant.exe"
     ) and not
      (process.code_signature.subject_name : ("Opera Norway AS", "Opera Software AS") and process.code_signature.trusted == true)
    ) or

    /* Whale Related Processes */
    (process.name : (
      "whale.exe", "whale_update.exe", "wusvc.exe"
     ) and not
      (process.code_signature.subject_name : "NAVER Corp." and process.code_signature.trusted == true)
    ) or

    /* Chromium-based Browsers processes */
    (process.name : (
      "chrmstp.exe", "notification_helper.exe", "elevation_service.exe"
     ) and not
      (process.code_signature.subject_name : (
        "Island Technology Inc.",
        "Citrix Systems, Inc.",
        "Brave Software, Inc.",
        "Google LLC",
        "Google Inc",
        "Microsoft Corporation",
        "NAVER Corp.",
        "AVG Technologies USA, LLC",
        "Avast Software s.r.o.",
        "PIRIFORM SOFTWARE LIMITED",
        "NortonLifeLock Inc.",
        "Opera Norway AS"
       ) and process.code_signature.trusted == true
      )
    )
  )

Framework: MITRE ATT&CK^TM

Tactic:
- Name: Defense Evasion
- ID: TA0005
- Reference URL: https://attack.mitre.org/tactics/TA0005/
Technique:
- Name: Masquerading
- ID: T1036
- Reference URL: https://attack.mitre.org/techniques/T1036/
Sub-technique:
- Name: Invalid Code Signature
- ID: T1036.001
- Reference URL: https://attack.mitre.org/techniques/T1036/001/
Sub-technique:
- Name: Match Legitimate Name or Location
- ID: T1036.005
- Reference URL: https://attack.mitre.org/techniques/T1036/005/
Tactic:
- Name: Persistence
- ID: TA0003
- Reference URL: https://attack.mitre.org/tactics/TA0003/
Technique:
- Name: Compromise Host Software Binary
- ID: T1554
- Reference URL: https://attack.mitre.org/techniques/T1554/

« Potential Local NTLM Relay via HTTP Potential Masquerading as Business App Installer »