Elastic Security Detection Rules

Potential Ransomware Behavior - High count of Readme files by System

Last updated 5 months ago on 2025-03-20
Created a year ago on 2024-05-03

About

This rule identifies a high number (20) of file creation event by the System virtual process from the same host and with same file name containing keywords similar to ransomware note files and all within a short time period.
Tags
Domain: EndpointOS: WindowsUse Case: Threat DetectionTactic: ImpactData Source: Elastic DefendData Source: Elastic EndgameData Source: Microsoft Defender for EndpointData Source: SysmonData Source: SentinelOneLanguage: kuery
Severity
high
Risk Score
73
MITRE ATT&CK™

Impact (TA0040)(opens in a new tab or window)

↳ Data Destruction (T1485)(opens in a new tab or window)

Lateral Movement (TA0008)(opens in a new tab or window)

↳ Remote Services (T1021)(opens in a new tab or window)

License
Elastic License v2(opens in a new tab or window)

Definition

Rule Type
Threshold Rule
Integration Pack
Prebuilt Security Detection Rules
Index Patterns
logs-endpoint.events.file-*winlogbeat-*logs-windows.sysmon_operational-*endgame-*logs-m365_defender.event-*logs-sentinel_one_cloud_funnel.*
Related Integrations

endpoint(opens in a new tab or window)

windows(opens in a new tab or window)

m365_defender(opens in a new tab or window)

sentinel_one_cloud_funnel(opens in a new tab or window)

Query
event.category:file and host.os.type:windows and process.pid:4 and event.action:creation and
 file.name:(*read*me* or *README* or *lock* or *LOCK* or *how*to* or *HOW*TO* or *@* or *recover* or *RECOVER* or *decrypt* or *DECRYPT* or *restore* or *RESTORE* or *FILES_BACK* or *files_back*)

Install detection rules in Elastic Security

Detect Potential Ransomware Behavior - High count of Readme files by System in the Elastic Security detection engine by installing this rule into your Elastic Stack.

To setup this rule, check out the installation guide for Prebuilt Security Detection Rules(opens in a new tab or window).