Security software that uses 'code hooking' opens the door to hackers

The flaws allow hackers to easily bypass exploit mitigations in the OS and third-party apps

Some of the intrusive techniques used by security, performance, virtualization and other types of programs to monitor third-party processes have introduced vulnerabilities that hackers can exploit.

Researchers from data exfiltration prevention company enSilo found six common security issues affecting over 15 products when they studied how software vendors use 'hooking' to inject code into a process in order to intercept, monitor or modify the potentially sensitive system API (application programming interface) calls made by that process.

Most of the flaws enSilo found allow attackers to easily bypass the anti-exploit mitigations available in Windows or third-party applications, allowing attackers to exploit vulnerabilities that they couldn't otherwise or whose exploitation would have been difficult. Other flaws allow attackers to remain undetected on victims' computers or to inject malicious code into any process running on them, the enSilo researchers said in a report sent via email that's scheduled to be published Tuesday.

The hooking method is used extensively in the antivirus world to monitor for potentially malicious behavior, but is also used by anti-exploitation, virtualization, performance monitoring and sandboxing applications. Some malware programs also hook browser processes to launch so-called Man-in-the-Browser attacks.

Antivirus programs accounted for most of the affected products the security company identified, but one vulnerability also exists in a commercial hooking engine developed by Microsoft and used by over 100 other software vendors.

EnSilo identified affected products from AVG, Kaspersky Lab, McAfee/Intel Security, Symantec, Trend Micro, Bitdefender, Citrix, Webroot, Avast, Emsisoft and Vera Security.

Some of these vendors have released fixes for the flaws, but patching is not easy because it often requires recompiling each affected product individually. Microsoft plans to release patches for its Microsoft Detours hooking engine in August, enSilo said. 

Bitdefender said it fixed the problem on Jan. 19, and has pushed the fix out to affected customers. Microsoft and Symantec did not immediately respond to a request for comment.

The researchers plan to release technical details of the vulnerabilities during the upcoming Black Hat security conference in Las Vegas in early August.

This is not the first time this type of security weakness has been introduced by antivirus products. Last year, the enSilo researchers found that products from Intel Security, Kaspersky Lab and AVG allocated a memory page with read, write and execute permissions to user-mode processes. This allowed attackers to bypass anti-exploitation protections such as address space layout randomization (ASLR) and data execution prevention (DEP) for third-party applications.

In fact, it was that discovery that fuelled this larger research into hooking implementations used by different products.

It's hard to estimate the number of vulnerable systems, but since the affected software includes the Microsoft Detours engine, the enSilo researchers believe that hundreds of thousands of users might be affected. According to them, the Detours vulnerability has existed for at least eight years.

"Companies using affected software should get patches from the vendors, if available," the enSilo researchers said. "Customers using software from the affected vendors should contact their vendors and demand that the software be patched."

Join the newsletter!

Error: Please check your email address.
Rocket to Success - Your 10 Tips for Smarter ERP System Selection
Keep up with the latest tech news, reviews and previews by subscribing to the Good Gear Guide newsletter.

Lucian Constantin

IDG News Service
Show Comments

Most Popular Reviews

Latest Articles

Resources

PCW Evaluation Team

Sarah Ieroianni

Brother QL-820NWB Professional Label Printer

The print quality also does not disappoint, it’s clear, bold, doesn’t smudge and the text is perfectly sized.

Ratchada Dunn

Sharp PN-40TC1 Huddle Board

The Huddle Board’s built in program; Sharp Touch Viewing software allows us to easily manipulate and edit our documents (jpegs and PDFs) all at the same time on the dashboard.

George Khoury

Sharp PN-40TC1 Huddle Board

The biggest perks for me would be that it comes with easy to use and comprehensive programs that make the collaboration process a whole lot more intuitive and organic

David Coyle

Brother PocketJet PJ-773 A4 Portable Thermal Printer

I rate the printer as a 5 out of 5 stars as it has been able to fit seamlessly into my busy and mobile lifestyle.

Kurt Hegetschweiler

Brother PocketJet PJ-773 A4 Portable Thermal Printer

It’s perfect for mobile workers. Just take it out — it’s small enough to sit anywhere — turn it on, load a sheet of paper, and start printing.

Matthew Stivala

HP OfficeJet 250 Mobile Printer

The HP OfficeJet 250 Mobile Printer is a great device that fits perfectly into my fast paced and mobile lifestyle. My first impression of the printer itself was how incredibly compact and sleek the device was.

Featured Content

Latest Jobs

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?