IMPORTANT: No additional bug fixes or documentation updates
will be released for this version. For the latest information, see the
current release documentation.
Unusual Process Extension
editUnusual Process Extension
editIdentifies processes running with unusual extensions that are not typically valid for Windows executables.
Rule type: eql
Rule indices:
- logs-endpoint.events.*
Severity: low
Risk score: 21
Runs every: 60m
Searches indices from: now-119m (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: Defense Evasion
- Data Source: Elastic Defend
- Rule Type: BBR
Version: 2
Rule authors:
- Elastic
Rule license: Elastic License v2
Rule query
editprocess where host.os.type == "windows" and event.type == "start" and
process.executable : "?*" and
not process.name : ("*.exe", "*.com", "*.scr", "*.tmp", "*.dat") and
not process.executable :
(
"MemCompression",
"Registry",
"vmmem",
"vmmemWSL",
"?:\\Program Files\\Dell\\SupportAssistAgent\\*.p5x",
"?:\\Program Files\\Docker\\Docker\\com.docker.service",
"?:\\Users\\*\\AppData\\Local\\Intel\\AGS\\Libs\\AGSRunner.bin"
) and
not (
(process.name : "C9632CF058AE4321B6B0B5EA39B710FE" and process.code_signature.subject_name == "Dell Inc") or
(process.name : "*.upd" and process.code_signature.subject_name == "Bloomberg LP") or
(process.name: "FD552E21-686E-413C-931D-3B82A9D29F3B" and process.code_signature.subject_name: "Adobe Inc.") or
(process.name: "3B91051C-AE82-43C9-BCEF-0309CD2DD9EB" and process.code_signature.subject_name: "McAfee, LLC")
)
Framework: MITRE ATT&CKTM
-
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/