Suspicious PrintSpooler Service Executable File Creation

Elastic Stack Serverless Security

Detects attempts to exploit privilege escalation vulnerabilities related to the Print Spooler service. For more information refer to the following CVE’s - CVE-2020-1048, CVE-2020-1337 and CVE-2020-1300 and verify that the impacted system is patched.

Rule type: eql

Rule indices:

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

Severity: high

Risk score: 73

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: 100

References:

• https://voidsec.com/cve-2020-1337-printdemon-is-dead-long-live-printdemon/
• https://www.thezdi.com/blog/2020/7/8/cve-2020-1300-remote-code-execution-through-microsoft-windows-cab-files

Tags:

• Elastic
• Host
• Windows
• Threat Detection
• Privilege Escalation

Version: 101

Rule authors:

• Elastic

Rule license: Elastic License v2

file where event.type == "creation" and
  process.name : "spoolsv.exe" and file.extension : "dll" and
  file.path : ("?:\\Windows\\System32\\*", "?:\\Windows\\SysWOW64\\*") and
  not file.path :
          ("?:\\WINDOWS\\SysWOW64\\PrintConfig.dll",
           "?:\\WINDOWS\\system32\\x5lrs.dll",
           "?:\\WINDOWS\\sysWOW64\\x5lrs.dll",
           "?:\\WINDOWS\\system32\\PrintConfig.dll")

Framework: MITRE ATT&CKTM

• Tactic:

  • Name: Privilege Escalation
  • ID: TA0004
  • Reference URL: https://attack.mitre.org/tactics/TA0004/

• Technique:

  • Name: Exploitation for Privilege Escalation
  • ID: T1068
  • Reference URL: https://attack.mitre.org/techniques/T1068/