Memory Dump File with Unusual Extension

Elastic Stack Serverless Security

Identifies the creation of a memory dump file with an unusual extension, which can indicate an attempt to disguise a memory dump as another file type to bypass security defenses.

Rule type: eql

Rule indices:

logs-endpoint.events.file-*

Severity: low

Risk score: 21

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: None

Tags:

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

Version: 2

Rule authors:

Elastic

Rule license: Elastic License v2

Rule query

		file where host.os.type == "windows" and event.type == "creation" and

  /* MDMP header */
  file.Ext.header_bytes : "4d444d50*" and
  not file.extension : ("dmp", "mdmp", "hdmp", "edmp", "full", "tdref", "cg", "tmp", "dat") and
  not
  (
    process.executable : "?:\\Program Files\\Endgame\\esensor.exe" and
    process.code_signature.trusted == true and length(file.extension) == 0
  ) and
  not
  (
    process.name : "System" and file.extension : "tmpscan"
  )

	

Framework: MITRE ATT&CKTM

Tactic:
- Name: Credential Access
- ID: TA0006
- Reference URL: https://attack.mitre.org/tactics/TA0006/
Technique:
- Name: OS Credential Dumping
- ID: T1003
- Reference URL: https://attack.mitre.org/techniques/T1003/
Sub-technique:
- Name: LSASS Memory
- ID: T1003.001
- Reference URL: https://attack.mitre.org/techniques/T1003/001/
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: Masquerade File Type
- ID: T1036.008
- Reference URL: https://attack.mitre.org/techniques/T1036/008/