Startup or Run Key Registry Modificationedit

Identifies run key or startup key registry modifications. In order to survive reboots and other system interrupts, attackers will modify run keys within the registry or leverage startup folder items as a form of persistence.

Rule type: eql

Rule indices:


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


  • Domain: Endpoint
  • OS: Windows
  • Use Case: Threat Detection
  • Tactic: Persistence
  • Resources: Investigation Guide
  • Data Source: Elastic Endgame
  • Data Source: Elastic Defend

Version: 111

Rule authors:

  • Elastic

Rule license: Elastic License v2

Investigation guideedit

Triage and analysis

Investigating Startup or Run Key Registry Modification

Adversaries may achieve persistence by referencing a program with a registry run key. Adding an entry to the run keys in the registry will cause the program referenced to be executed when a user logs in. These programs will executed under the context of the user and will have the account’s permissions. This rule looks for this behavior by monitoring a range of registry run keys.

Note: This investigation guide uses the Osquery Markdown Plugin introduced in Elastic Stack version 8.5.0. Older Elastic Stack versions will display unrendered Markdown in this guide.

Possible investigation steps

  • Investigate the process execution chain (parent process tree) for unknown processes. Examine their executable files for prevalence, whether they are located in expected locations, and if they are signed with valid digital signatures.
  • Investigate other alerts associated with the user/host during the past 48 hours.
  • Validate if the activity is not related to planned patches, updates, network administrator activity, or legitimate software installations.
  • Assess whether this behavior is prevalent in the environment by looking for similar occurrences across hosts.
  • Examine the host for derived artifacts that indicate suspicious activities:
  • Analyze the process executable using a private sandboxed analysis system.
  • Observe and collect information about the following activities in both the sandbox and the alert subject host:
  • Attempts to contact external domains and addresses.
  • Use the Elastic Defend network events to determine domains and addresses contacted by the subject process by filtering by the process' process.entity_id.
  • Examine the DNS cache for suspicious or anomalous entries.
  • !{osquery{"label":"Osquery - Retrieve DNS Cache","query":"SELECT * FROM dns_cache"}}
  • Use the Elastic Defend registry events to examine registry keys accessed, modified, or created by the related processes in the process tree.
  • Examine the host services for suspicious or anomalous entries.
  • !{osquery{"label":"Osquery - Retrieve All Services","query":"SELECT description, display_name, name, path, pid, service_type, start_type, status, user_account FROM services"}}
  • !{osquery{"label":"Osquery - Retrieve Services Running on User Accounts","query":"SELECT description, display_name, name, path, pid, service_type, start_type, status, user_account FROM services WHERE\nNOT (user_account LIKE %LocalSystem OR user_account LIKE %LocalService OR user_account LIKE %NetworkService OR\nuser_account == null)\n"}}
  • !{osquery{"label":"Osquery - Retrieve Service Unsigned Executables with Virustotal Link","query":"SELECT concat(, sha1) AS VtLink, name, description, start_type, status, pid,\nservices.path FROM services JOIN authenticode ON services.path = authenticode.path OR services.module_path =\nauthenticode.path JOIN hash ON services.path = hash.path WHERE authenticode.result != trusted\n"}}
  • Retrieve the files' SHA-256 hash values using the PowerShell Get-FileHash cmdlet and search for the existence and reputation of the hashes in resources like VirusTotal, Hybrid-Analysis, CISCO Talos,, etc.
  • Investigate potentially compromised accounts. Analysts can do this by searching for login events (for example, 4624) to the target host after the registry modification.

False positive analysis

  • There is a high possibility of benign legitimate programs being added to registry run keys. This activity could be based on new software installations, patches, or any kind of network administrator related activity. Before undertaking further investigation, verify that this activity is not benign.

Related rules

  • Suspicious Startup Shell Folder Modification - c8b150f0-0164-475b-a75e-74b47800a9ff
  • Persistent Scripts in the Startup Directory - f7c4dc5a-a58d-491d-9f14-9b66507121c0
  • Startup Folder Persistence via Unsigned Process - 2fba96c0-ade5-4bce-b92f-a5df2509da3f
  • Startup Persistence by a Suspicious Process - 440e2db4-bc7f-4c96-a068-65b78da59bde

Response and remediation

  • Initiate the incident response process based on the outcome of the triage.
  • Isolate the involved host to prevent further post-compromise behavior.
  • If the triage identified malware, search the environment for additional compromised hosts.
  • Implement temporary network rules, procedures, and segmentation to contain the malware.
  • Stop suspicious processes.
  • Immediately block the identified indicators of compromise (IoCs).
  • Inspect the affected systems for additional malware backdoors like reverse shells, reverse proxies, or droppers that attackers could use to reinfect the system.
  • Remove and block malicious artifacts identified during triage.
  • Investigate credential exposure on systems compromised or used by the attacker to ensure all compromised accounts are identified. Reset passwords for these accounts and other potentially compromised credentials, such as email, business systems, and web services.
  • Run a full antimalware scan. This may reveal additional artifacts left in the system, persistence mechanisms, and malware components.
  • Determine the initial vector abused by the attacker and take action to prevent reinfection through the same vector.
  • Using the incident response data, update logging and audit policies to improve the mean time to detect (MTTD) and the mean time to respond (MTTR).

Rule queryedit

registry where host.os.type == "windows" and != null and
 registry.path : (
     /* Machine Hive */
     "HKLM\\Software\\Microsoft\\Windows NT\\CurrentVersion\\Winlogon\\Shell\\*",
     /* Users Hive */
     "HKEY_USERS\\*\\Software\\Microsoft\\Windows NT\\CurrentVersion\\Winlogon\\Shell\\*"
     ) and
  /* add common legitimate changes without being too restrictive as this is one of the most abused AESPs */
  not : "ctfmon.exe /n" and
  not (registry.value : "Application Restart #*" and : "csrss.exe") and
  not : ("S-1-5-18", "S-1-5-19", "S-1-5-20") and
  not : ("?:\\Program Files\\*.exe", "?:\\Program Files (x86)\\*.exe") and
  not process.executable : ("?:\\Windows\\System32\\msiexec.exe", "?:\\Windows\\SysWOW64\\msiexec.exe") and
  not (
    /* Logitech G Hub */
      process.code_signature.trusted == true and process.code_signature.subject_name == "Logitech Inc" and
      ( : "lghub_agent.exe" and : (
          "\"?:\\Program Files\\LGHUB\\lghub.exe\" --background",
          "\"?:\\Program Files\\LGHUB\\system_tray\\lghub_system_tray.exe\" --minimized"
      ) or
      ( : "LogiBolt.exe" and : (
          "?:\\Program Files\\Logi\\LogiBolt\\LogiBolt.exe --startup",
          "?:\\Users\\*\\AppData\\Local\\Logi\\LogiBolt\\LogiBolt.exe --startup"
    ) or

    /* Google Drive File Stream, Chrome, and Google Update */
      process.code_signature.trusted == true and process.code_signature.subject_name == "Google LLC" and
      ( : "GoogleDriveFS.exe" and : (
        "\"?:\\Program Files\\Google\\Drive File Stream\\*\\GoogleDriveFS.exe\" --startup_mode"
        ) or : "chrome.exe" and : (
          "\"?:\\Program Files\\Google\\Chrome\\Application\\chrome.exe\" --no-startup-window /prefetch:5",
          "\"?:\\Program Files (x86)\\Google\\Chrome\\Application\\chrome.exe\" --no-startup-window /prefetch:5"
        ) or : "GoogleUpdate.exe" and : (
    ) or

    /* MS Programs */
      process.code_signature.trusted == true and process.code_signature.subject_name in ("Microsoft Windows", "Microsoft Corporation") and
      ( : "msedge.exe" and : (
          "\"?:\\Program Files (x86)\\Microsoft\\Edge\\Application\\msedge.exe\" --no-startup-window --win-session-start /prefetch:5",
          "\"C:\\Program Files (x86)\\Microsoft\\Edge\\Application\\msedge.exe\" --win-session-start",
          "\"C:\\Program Files (x86)\\Microsoft\\Edge\\Application\\msedge.exe\" --no-startup-window --win-session-start"
        ) or : ("Update.exe", "Teams.exe") and : (
          "?:\\Users\\*\\AppData\\Local\\Microsoft\\Teams\\Update.exe --processStart \"Teams.exe\" --process-start-args \"--system-initiated\"",
          "?:\\ProgramData\\*\\Microsoft\\Teams\\Update.exe --processStart \"Teams.exe\" --process-start-args \"--system-initiated\""
        ) or : "OneDriveStandaloneUpdater.exe" and : (
        ) or : "OneDriveSetup.exe" and
 : (
            "?:\\Windows\\system32\\cmd.exe /q /c * \"?:\\Users\\*\\AppData\\Local\\Microsoft\\OneDrive\\*\"",
            "?:\\Program Files (x86)\\Microsoft OneDrive\\OneDrive.exe /background*",
            "\"?:\\Program Files (x86)\\Microsoft OneDrive\\OneDrive.exe\" /background*",
            "?:\\Program Files\\Microsoft OneDrive\\OneDrive.exe /background *",
          ) or : "OneDrive.exe" and : (
          "\"?:\\Program Files\\Microsoft OneDrive\\OneDrive.exe\" /background",
          "\"?:\\Program Files (x86)\\Microsoft OneDrive\\OneDrive.exe\" /background",
          "\"?:\\Users\\*\\AppData\\Local\\Microsoft\\OneDrive\\OneDrive.exe\" /background"
        ) or : "Microsoft.SharePoint.exe" and : (
        ) or : "MicrosoftEdgeUpdate.exe" and : (
        ) or

        process.executable : "?:\\Program Files (x86)\\Microsoft\\EdgeWebView\\Application\\*\\Installer\\setup.exe" and : (
          "\"?:\\Program Files (x86)\\Microsoft\\EdgeWebView\\Application\\*\\Installer\\setup.exe\" --msedgewebview --delete-old-versions --system-level --verbose-logging --on-logon"
    ) or

    /* Slack */
      process.code_signature.trusted == true and process.code_signature.subject_name in (
       "Slack Technologies, Inc.", "Slack Technologies, LLC"
      ) and : "slack.exe" and : (
        "\"?:\\Users\\*\\AppData\\Local\\slack\\slack.exe\" --process-start-args --startup",
        "\"?:\\ProgramData\\*\\slack\\slack.exe\" --process-start-args --startup",
        "\"?:\\Program Files\\Slack\\slack.exe\" --process-start-args --startup"
    ) or

    /* Cisco */
      process.code_signature.trusted == true and process.code_signature.subject_name in ("Cisco WebEx LLC", "Cisco Systems, Inc.") and
      ( : "WebexHost.exe" and : (
          "\"?:\\Users\\*\\AppData\\Local\\WebEx\\WebexHost.exe\" /daemon /runFrom=autorun"
      ) or
      ( : "CiscoJabber.exe" and : (
          "\"?:\\Program Files (x86)\\Cisco Systems\\Cisco Jabber\\CiscoJabber.exe\" /min"
    ) or

    /* Loom */
      process.code_signature.trusted == true and process.code_signature.subject_name == "Loom, Inc." and : "Loom.exe" and : (
        "?:\\Users\\*\\AppData\\Local\\Programs\\Loom\\Loom.exe --process-start-args \"--loomHidden\""
    ) or

    /* Adobe */
      process.code_signature.trusted == true and process.code_signature.subject_name == "Adobe Inc." and : ("Acrobat.exe", "FlashUtil32_*_Plugin.exe") and : (
        "\"?:\\Program Files\\Adobe\\Acrobat DC\\Acrobat\\AdobeCollabSync.exe\"",
        "\"?:\\Program Files (x86)\\Adobe\\Acrobat DC\\Acrobat\\AdobeCollabSync.exe\"",
        "?:\\WINDOWS\\SysWOW64\\Macromed\\Flash\\FlashUtil32_*_Plugin.exe -update plugin"
    ) or

    /* CCleaner */
      process.code_signature.trusted == true and process.code_signature.subject_name == "PIRIFORM SOFTWARE LIMITED" and : ("CCleanerBrowser.exe", "CCleaner64.exe") and : (
        "\"C:\\Program Files (x86)\\CCleaner Browser\\Application\\CCleanerBrowser.exe\" --check-run=src=logon --auto-launch-at-startup --profile-directory=\"Default\"",
        "\"C:\\Program Files\\CCleaner\\CCleaner64.exe\" /MONITOR"
    ) or

    /* Opera */
      process.code_signature.trusted == true and process.code_signature.subject_name == "Opera Norway AS" and : "opera.exe" and : (
        "?:\\Users\\*\\AppData\\Local\\Programs\\Opera GX\\launcher.exe"
    ) or

    /* Avast */
      process.code_signature.trusted == true and process.code_signature.subject_name == "Avast Software s.r.o." and : "AvastBrowser.exe" and : (
        "\"?:\\Users\\*\\AppData\\Local\\AVAST Software\\Browser\\Application\\AvastBrowser.exe\" --check-run=src=logon --auto-launch-at-startup*",
        "\"?:\\Program Files (x86)\\AVAST Software\\Browser\\Application\\AvastBrowser.exe\" --check-run=src=logon --auto-launch-at-startup*",
    ) or

    /* Grammarly */
      process.code_signature.trusted == true and process.code_signature.subject_name == "Grammarly, Inc." and : "GrammarlyInstaller.exe" and : (