SVG File Used for HTML Smuggling Payload

This rule detects the use of SVG files for HTML smuggling payloads. Specifically, it looks for HTTP responses containing an SVG file ('.svg' in the URI) that also contain '<script' and 'Blob(' within its data. This combination is indicative of an HTML smuggling technique where malicious content is hidden within a seemingly innocuous SVG file and then processed by JavaScript to construct a malicious payload, often a file download.