Suspicious Browser Child Process

edit

Identifies the execution of a suspicious browser child process. Adversaries may gain access to a system through a user visiting a website over the normal course of browsing. With this technique, the user’s web browser is typically targeted for exploitation.

Rule type: eql

Rule indices:

  • logs-endpoint.events.*

Severity: high

Risk score: 73

Runs every: 5 minutes

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

Maximum alerts per execution: 100

References:

Tags:

  • Elastic
  • Host
  • macOS
  • Threat Detection
  • Initial Access
  • Execution

Version: 100 (version history)

Added (Elastic Stack release): 7.12.0

Last modified (Elastic Stack release): 8.5.0

Rule authors: Elastic

Rule license: Elastic License v2

Rule query

edit
process where event.type in ("start", "process_started") and
process.parent.name : ("Google Chrome", "Google Chrome Helper*",
"firefox", "Opera", "Safari", "com.apple.WebKit.WebContent",
"Microsoft Edge") and process.name : ("sh", "bash", "dash", "ksh",
"tcsh", "zsh", "curl", "wget", "python*", "perl*", "php*",
"osascript", "pwsh") and process.command_line != null and not
process.command_line : "*/Library/Application
Support/Microsoft/MAU*/Microsoft
AutoUpdate.app/Contents/MacOS/msupdate*" and not process.args :
( "hw.model", "IOPlatformExpertDevice",
"/Volumes/Google Chrome/Google
Chrome.app/Contents/Frameworks/*/Resources/install.sh", "--
defaults-torrc", "*Chrome.app", "Framework.framework/Versi
ons/*/Resources/keystone_promote_preflight.sh",
"/Users/*/Library/Application
Support/Google/Chrome/recovery/*/ChromeRecovery", "$DISPLAY",
"*GIO_LAUNCHED_DESKTOP_FILE_PID=$$*", "/opt/homebrew/*",
"/usr/local/*brew*" )

Threat mapping

edit

Framework: MITRE ATT&CKTM

Rule version history

edit
Version 100 (8.5.0 release)
  • Updated query, changed from:

    process where event.type in ("start", "process_started") and
    process.parent.name : ("Google Chrome", "Google Chrome Helper*",
    "firefox", "Opera", "Safari", "com.apple.WebKit.WebContent",
    "Microsoft Edge") and process.name : ("sh", "bash", "dash", "ksh",
    "tcsh", "zsh", "curl", "wget", "python*", "perl*", "php*",
    "osascript", "pwsh") and process.command_line != null and not
    process.args : ( "/Library/Application
    Support/Microsoft/MAU*/Microsoft
    AutoUpdate.app/Contents/MacOS/msupdate", "hw.model",
    "IOPlatformExpertDevice", "/Volumes/Google Chrome/Google
    Chrome.app/Contents/Frameworks/*/Resources/install.sh", "--
    defaults-torrc", "Chrome.app", "Framework.framework/Vers
    ions/*/Resources/keystone_promote_preflight.sh",
    "/Users/*/Library/Application
    Support/Google/Chrome/recovery/*/ChromeRecovery", "$DISPLAY",
    "GIO_LAUNCHED_DESKTOP_FILE_PID=$$" )
Version 2 (8.4.0 release)
  • Formatting only