Security builder & leader

Time to Let Go of Java in the Web Browser: How to Disable It

Java exploits have become the top moneymaker for exploit kit authors, yet few people regularly use Java in browsers. The likelihood of being targeted overpowers the benefits. Disable Java in browsers or use NoScript to allowlist sites; keep JRE patched with Secunia PSI if you can't remove it.

I agree with Brian Krebs: Having Java Runtime Environment (JRE) as part of your web browser has become a major liability. As he put it, “attacks against Java vulnerabilities have fast emerged as the top moneymaker for authors of the best-selling ‘exploit kits,’ commercial crimeware designed to be stitched into hacked or malicious sites and exploit a variety of Web-browser vulnerabilities.”

I often see Java targeted by exploit kits; yet, not many individuals actually use Java in their browser on regular basis. We’re at a point when the the likelihood of it being targeted by a malicious website overpowers the benefits that most people derive from having JRE installed.

To quickly check whether Java support is enabled in your browser, visit Oracle’s How do I test whether Java is working on my computer? page. If you see the message “Your Java is working,” then Java is installed. The lack of this message implies that Java cannot be automatically invoked through the browser, which—in the context of this note—is a good thing.

Truth be told, some useful applications are still written in Java and expect to be invoked through the browser. If you cannot simply uninstall Java from your system, you have a few options to limit your exposure to Java exploits:

If you cannot uninstall or disable Java access through your browser, be sure to keep your JRE up to date with the latest security patches. The best way to accomplish this is on a single end-user’s system probably with Secunia Personal Software Inspector (PSI).

Do you have other tips for controlling access to Java through the web browser?

About the Author

Lenny Zeltser is a cybersecurity executive with deep technical roots, product management experience, and a business mindset. As CISO at Axonius, he leads the security and IT program, focusing on trust and growth. He is also a Faculty Fellow at SANS Institute and the creator of REMnux, a popular Linux toolkit for malware analysis. Lenny shares his perspectives on security leadership and technology at zeltser.com.

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