Why browser extensions are a major security risk and what you can do about it

Browser extensions pose serious security risks because they run inside the browser process with broad permissions, enabling credential theft, session cookie exfiltration, and silent malicious updates. Real-world breaches like Vercel and Cyberhaven illustrate how extensions serve as entry points for attackers. The Chrome Web Store's minimal vetting, silent auto-updates, and the ability to transfer extension ownership make traditional allowlist-based controls inadequate. Practical mitigations include auditing installed extensions and their permissions, using browser profiles to isolate sensitive work, and at the organizational level, deploying behavior-based monitoring with live threat intelligence feeds rather than static allowlists. Aikido Endpoint is presented as a dedicated solution for this problem.