Potential Cookies Theft via Browser Debugging

Elastic Stack Serverless Security

Identifies the execution of a Chromium based browser with the debugging process argument, which may indicate an attempt to steal authentication cookies. An adversary may steal web application or service session cookies and use them to gain access web applications or Internet services as an authenticated user without needing credentials.

Rule type: eql

Rule indices:

• auditbeat-*
• winlogbeat-*
• logs-endpoint.events.*
• logs-windows.*

Severity: medium

Risk score: 47

Runs every: 5m

Searches indices from: now-9m (https://www.elastic.co/guide/en/elasticsearch/reference/current/common-options.html#date-math[Date Math format], see also Additional look-back time)

Maximum alerts per execution: 33

References:

• https://github.com/defaultnamehere/cookie_crimes
• https://embracethered.com/blog/posts/2020/cookie-crimes-on-mirosoft-edge/
• https://github.com/rapid7/metasploit-framework/blob/master/documentation/modules/post/multi/gather/chrome_cookies.md
• https://posts.specterops.io/hands-in-the-cookie-jar-dumping-cookies-with-chromiums-remote-debugger-port-34c4f468844e

Tags:

• Elastic
• Host
• Linux
• Windows
• macOS
• Threat Detection
• Credential Access

Version: 2

Rule authors:

• Elastic

Rule license: Elastic License v2

If enabling an EQL rule on a non-elastic-agent index (such as beats) for versions <8.2, events will not define event.ingested and default fallback for EQL rules was not added until 8.2, so you will need to add a custom pipeline to populate event.ingested to @timestamp for this rule to work.

process where event.type in ("start", "process_started", "info") and
  process.name in (
             "Microsoft Edge",
             "chrome.exe",
             "Google Chrome",
             "google-chrome-stable",
             "google-chrome-beta",
             "google-chrome",
             "msedge.exe") and
   process.args : ("--remote-debugging-port=*",
                   "--remote-debugging-targets=*",
                   "--remote-debugging-pipe=*") and
   process.args : "--user-data-dir=*" and not process.args:"--remote-debugging-port=0"

Framework: MITRE ATT&CKTM

• Tactic:

  • Name: Credential Access
  • ID: TA0006
  • Reference URL: https://attack.mitre.org/tactics/TA0006/

• Technique:

  • Name: Steal Web Session Cookie
  • ID: T1539
  • Reference URL: https://attack.mitre.org/techniques/T1539/