Download Bar
April 23, 2024
In Chromium-based browsers, when a file was downloaded, a preview of the download process appeared in a bar at the bottom, integrated into the browser window. By monitoring the window height, attackers could detect whether the “download bar” opened:
// Read the current height of the window
var screenHeight = window.innerHeight;
// Load the page that may or may not trigger the download
window.open('https://example.org');
// Wait for the tab to load
setTimeout(() => {
// If the download bar appears, the height of all tabs will be smaller
if (window.innerHeight < screenHeight) {
console.log('Download bar detected');
} else {
console.log('Download bar not detected');
}
}, 2000);
important
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