Unusual Web Request

Last updated 7 months ago on 2025-01-15
Created 5 years ago on 2020-03-25

About

A machine learning job detected a rare and unusual URL that indicates unusual web browsing activity. This can be due to initial access, persistence, command-and-control, or exfiltration activity. For example, in a strategic web compromise or watering hole attack, when a trusted website is compromised to target a particular sector or organization, targeted users may receive emails with uncommon URLs for trusted websites. These URLs can be used to download and run a payload. When malware is already running, it may send requests to uncommon URLs on trusted websites the malware uses for command-and-control communication. When rare URLs are observed being requested for a local web server by a remote source, these can be due to web scanning, enumeration or attack traffic, or they can be due to bots and web scrapers which are part of common Internet background traffic.
Tags
Use Case: Threat DetectionRule Type: MLRule Type: Machine LearningTactic: Command and Control
Severity
low
Risk Score
21
MITRE ATT&CK™

Command and Control (TA0011)(opens in a new tab or window)

False Positive Examples
Web activity that occurs rarely in small quantities can trigger this alert. Possible examples are browsing technical support or vendor URLs that are used very sparsely. A user who visits a new and unique web destination may trigger this alert when the activity is sparse. Web applications that generate URLs unique to a transaction may trigger this when they are used sparsely. Web domains can be excluded in cases such as these.
License
Elastic License v2(opens in a new tab or window)

Definition

Rule Type
Machine Learning
Integration Pack
Prebuilt Security Detection Rules
Related Integrations

endpoint(opens in a new tab or window)

network_traffic(opens in a new tab or window)

Query

Install detection rules in Elastic Security

Detect Unusual Web Request 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).