Elastic Security Detection Rules

Potential Web Shell ASPX File Creation

Last updated 25 days ago on 2025-07-24
Created 25 days ago on 2025-07-24

About

Identifies the creation of ASPX files in specific directories that are commonly targeted by attackers to deploy web shells.
Tags
Domain: EndpointOS: WindowsUse Case: Threat DetectionTactic: PersistenceData Source: Elastic EndgameData Source: Elastic DefendData Source: SysmonData Source: SentinelOneData Source: Microsoft Defender for EndpointData Source: CrowdstrikeLanguage: eql
Severity
low
Risk Score
21
MITRE ATT&CK™

Persistence (TA0003)(opens in a new tab or window)

↳ Server Software Component (T1505)(opens in a new tab or window)

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

Definition

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

endpoint(opens in a new tab or window)

windows(opens in a new tab or window)

sentinel_one_cloud_funnel(opens in a new tab or window)

m365_defender(opens in a new tab or window)

crowdstrike(opens in a new tab or window)

Query
file where host.os.type == "windows" and event.type != "deletion" and
  file.extension : "aspx" and
  file.path : "?:\\Program Files\\Common Files\\Microsoft Shared\\Web Server Extensions\\*" and
  not process.executable: "?:\\Windows\\System32\\msiexec.exe"

Install detection rules in Elastic Security

Detect Potential Web Shell ASPX File Creation 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).