Attackers can reportedly hijack security products via Microsoft Application Verifier. What does this tool do? How...
By submitting your personal information, you agree that TechTarget and its partners may contact you regarding relevant content, products and special offers.
can we stop malicious use of this tool?
Legitimate developers use Microsoft Application Verifier to find programming errors in their applications. The tool has been available since the days of Windows XP. The vertification tool is part of the Windows Software Development Kit, not the Debugging Tools for Windows.
Flaws in the Microsoft Application Verifier enable hackers to launch DoubleAgent attacks against antivirus products. They can take full control of Norton AntiVirus, for example, and use it as ransomware to encrypt or delete user files on a desktop.
The attack begins with the tool loading a so-called verifier provider dynamic link library (DLL) into the targeted application's process for runtime testing. After creating the verifier tool, the DLL is added to the Windows Registry as a provider DLL for a specified process. Windows then automatically injects the DLL into all the processes with the product's registered name.
Some antivirus vendors try to protect their products with the registry keys associated with their processes. The researchers at Cybellum, an Israeli company that specializes in zero-day prevention, easily bypassed a product's self-protection mechanism (the technique worked on all major antivirus products, according to the company). The researchers injected arbitrary code and registered a malicious DLL for a process associated with a product.
Check for the verification tool's patches
Not all impacted antivirus vendors have released patches for the Microsoft Application Verifier vulnerability. Those vendors that have released patches include Malwarebytes, AVG and Kaspersky Lab. Although the Comodo antivirus product was slightly more difficult to defeat, a different unreleased proof of concept has been used for the DoubleAgent attack.
Microsoft takes a different approach to protecting antimalware services. It adds another layer of defense by implementing Windows Defender Security Center in Windows 8.1 and beyond. You can view the status of antivirus products, firewall and network protection, app and browser controls, and device performance and health.
Before you update your favorite antivirus product, visit the vendor's website and the Common Vulnerabilities and Exposures website for the latest reports on the product's vulnerabilities and patches.
Ask the expert:
Want to ask Judith Myerson a question about security? Submit your question now via email. (All questions are anonymous.)
Learn more about the effects vulnerabilities in antivirus products have on the industry
Find out what enterprises can do about antivirus vulnerabilities
Get a better understanding of the behavioral detection of antivirus
Dig Deeper on Hacker tools and techniques: Underground hacking sites
Related Q&A from Judith Myerson
A patch was issued for the Dirty COW vulnerability, but researchers later discovered problems with the patch. Expert Judith Myerson explains what ...continue reading
Getting firewall settings right is one of the most basic ways to protect enterprise data from accidental exposures. Expert Judith Myerson discusses ...continue reading
Expert Judith Myerson explains how IP theft can happen despite the cryptographic protections in IEEE standard P1735, as well as what can be done to ...continue reading
Have a question for an expert?
Please add a title for your question
Get answers from a TechTarget expert on whatever's puzzling you.