Tainted Canvas -
This feature protects user privacy by preventing malicious websites from "stealing" sensitive images (like bank statements or private photos) that might be cached or authenticated in a user's browser. Without this, a script could draw a private image to a canvas, read its pixels, and send that data to a third-party server. How to Fix It (CORS) cookies - Why is a "tainted canvas" a risk?
Once a canvas is "tainted," it is no longer considered "origin-clean," and the browser blocks functions that allow you to read its pixel data: Tainted Canvas
A is a security feature in web browsers that prevents the unauthorized extraction of image data from a canvas element . It occurs automatically when an image or video from a different domain (origin) is drawn onto a without proper authorization. Key Effects of Tainting This feature protects user privacy by preventing malicious
: Attempting to use getImageData() will throw a SecurityError . Once a canvas is "tainted," it is no
: The content remains visible to the user, but it cannot be programmatically read back or saved by scripts. Why It Exists
: You cannot use toDataURL() , toBlob() , or captureStream() .