The hypothesis is that the detected jQuery code may be used by adversaries to execute arbitrary commands or escalate privileges through script injection. SOC teams should proactively hunt for this behavior in Azure Sentinel to identify potential web-based attacks that leverage compromised JavaScript libraries for lateral movement or persistence.
YARA Rule
rule jquery_code_su {
strings: $ = "105,102,40,40,110,101,119,32,82,101,103,69,120,112,40,39,111,110,101,112,97,103,101"
condition: any of them
}
This YARA rule can be deployed in the following contexts:
Scenario: Legitimate jQuery Code Update via Package Manager
Description: A system administrator uses npm or yarn to update jQuery code in a web application.
Filter/Exclusion: Check for presence of npm or yarn in the command line context, or filter by known package update scripts.
Scenario: Scheduled Job for jQuery-Based Reporting Tool
Description: A scheduled job runs a reporting tool (e.g., Tableau, Power BI, or Crystal Reports) that uses jQuery for client-side rendering.
Filter/Exclusion: Exclude processes associated with scheduled reporting tools or filter by known reporting service executables.
Scenario: Admin Task to Generate Static HTML Pages with jQuery
Description: An admin uses a tool like Jekyll, Gulp, or Webpack to generate static HTML pages that include jQuery for dynamic content.
Filter/Exclusion: Filter by known static site generators or build tools, or check for presence of Jekyll, Gulp, or Webpack in the process tree.
Scenario: jQuery Used in Internal Web Application Development
Description: Developers use jQuery in an internal web app (e.g., built with React, Vue, or Angular) for UI interactions.
Filter/Exclusion: Filter by known development frameworks or check for presence of development tools like webpack-dev-server or vite.
Scenario: jQuery Included in Third-Party Library for Legacy System
Description: A legacy system uses a third-party library (e.g., jQuery UI, Bootstrap, or Chart.js) that includes jQuery as a dependency.
Filter/Exclusion: Exclude known third-party libraries or filter by presence of jQuery UI, Bootstrap, or Chart.js in the file context.