Browser extensions can enhance productivity and personalise your online experience, but they also come with hidden dangers. While many users trust extensions from official browser stores, cybercriminals often disguise malicious code in seemingly helpful tools like ad blockers, PDF converters, or even security apps. Once installed, these extensions can harvest sensitive data, including login credentials, browsing history, and session cookies. They may even enable remote access to your device making everything on it freely available to the cybercriminal.
A 2023 study found that over half of 300,000 browser extensions used in corporate environments were high risk. Cybercriminals are finding more inventive ways to make their illegitimate browser add-ons available to unsuspecting users, so this number has most likely not reduced since then.
Threats can come from extensions bundled with other software, shared via deceptive links, or side-loaded from unofficial sources bypassing security checks. They may have even made it through official browser store security checks and look very similar to the real deal.
How to Stay Safe…
Considering the following steps will go a long way to reducing the chance of installing a malicious extension:
- Install only trusted extensions: Stick to well-reviewed tools from reputable developers and organisations, and avoid obscure or bundled software.
- Review and remove unused extensions: Periodically check your browser to eliminate anything you no longer use or recognise.
- Avoid side-loading: Never install extensions from unofficial sources or links shared via email or social media.
- Limit permissions: Be cautious about what data and access you grant to extensions.
Boost Your Browser Security…
Beyond managing extensions, there are several ways to strengthen your browser’s defences:
- Keep your browser updated: Ensure you're always using the latest version, which includes patches for known vulnerabilities.
- Enable multi-factor authentication (MFA): This adds a critical layer of protection to your online accounts, even if an extension compromises your passwords.
- Use secure browser modes: Some security vendors offer hardened browsing environments, ideal for sensitive activities like banking or crypto transactions.
- Turn on Enhanced Safe Browsing: Available in browsers like Chrome, this feature helps detect and block malicious sites before they can do harm.
- Install reputable security software: A good antivirus or endpoint protection suite can detect suspicious activity and prevent malware infections. Regular scans are essential to catch threats early.