Dark Reading is part of the Informa Tech Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them.Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 8860726.

Vulnerabilities / Threats

8/22/2019
06:30 PM
Connect Directly
Twitter
LinkedIn
RSS
E-Mail
50%
50%

New Malware Variant Targets Old Adobe, Office Vulnerabilities

Criminals appear to have developed it knowing some users have not patched or updated to newer versions, Trend Micro says.

Organizations that do not patch critical vulnerabilities in the software they use can remain exposed to attacks indefinitely.

A case in point is a new malware variant that researchers at Trend Micro discovered targeting vulnerabilities that were discovered more than six years ago in Adobe Acrobat, Adobe Reader, and Microsoft Office software. Both companies had issued patches.

The malware is a variant of the Asruex Backdoor associated with DarkHotel, a group known for targeting business hotel visitors via hotel Wi-Fi networks. Asruex has been around since at least 2015 and allows attackers to take complete remote control of infected systems. It infects systems via a shortcut file, which, when opened, executes a PowerShell command that ultimately results in Asruex being downloaded on the system. The malware is designed to spread through network drives and removable drives, Trend Micro explained in an advisory this week.

The variant using the patched vulnerabilities itself, however, only surfaced about a year ago. It seems explicitly designed to target organizations using unpatched versions of Adobe Reader 9.x up to before 9.4 and Acrobat versions 8.x up to before 8.2.5 on Windows and Mac OS X, Trend Micro says. "Because of this unique infection capability, security researchers might not consider checking files for an Asruex infection and continue to watch out for its backdoor abilities exclusively," Trend Micro warned.

The impacted versions of both the Adobe and Microsoft software are no longer supported.

Trend Micro researchers found the variant in a PDF file that had been infected with Asruex.  Their analysis showed the variant is designed to exploit two old vulnerabilities: a 2012 critical buffer-overflow issue in an ActiveX component in MS Office versions 2003, 2007, and 2010 that enabled remote code execution (CVE-2012-0158); and a 2010 stack-based buffer overflow in the Adobe products that could be used to inject code into PDFs (CVE-2010-2883). The Adobe flaw was a zero-day and was already being actively exploited in the wild when it was first disclosed.

In the advisory, Trend Micro described the Asruex variant as using infected PDF files and Word documents to drop and execute the malware on systems running unpatched versions of the vulnerable software. 

When the infector is executed on vulnerable versions of Adobe Reader and Adobe Acrobat, it displays the content of the original PDF file while silently dropping the malware in the background. The malware contains several anti-bugging and anti-emulation features and can detect if it is running in a sandbox environment, Trend Micro says.

According to the security vendor, the Asruex variant it discovered uses a special template to exploit the Office vulnerability to infect Word documents. As with PDF files, the variant allows attackers to execute arbitrary files on a system, but with a Word document. When the Word infector is executed, it runs in the background while displaying the original content of the Word document to trick users into believing everything is normal, Trend Micro said.

The Asruex variant poses a challenge for organizations still using versions of the software the malware is targeting, Trend Micro said. "Understandably, this could pose a challenge for organizations as updating widely used software could result in downtime of critical servers, and it could be costly and time consuming," the security vendor said. 

Such malware highlight the need for organizations to follow best practices when it comes to patching and updating critical software, it added.

Related Content:

Check out The Edge, Dark Reading's new section for features, threat data, and in-depth perspectives. Today's top story: "You Gotta Reach 'Em to Teach 'Em."

 

Jai Vijayan is a seasoned technology reporter with over 20 years of experience in IT trade journalism. He was most recently a Senior Editor at Computerworld, where he covered information security and data privacy issues for the publication. Over the course of his 20-year ... View Full Bio

Comment  | 
Print  | 
More Insights
Comments
Newest First  |  Oldest First  |  Threaded View
Register for Dark Reading Newsletters
White Papers
Video
Cartoon Contest
Write a Caption, Win a Starbucks Card! Click Here
Latest Comment: Our Endpoint Protection system is a little outdated... 
Current Issue
The Year in Security: 2019
This Tech Digest provides a wrap up and overview of the year's top cybersecurity news stories. It was a year of new twists on old threats, with fears of another WannaCry-type worm and of a possible botnet army of Wi-Fi routers. But 2019 also underscored the risk of firmware and trusted security tools harboring dangerous holes that cybercriminals and nation-state hackers could readily abuse. Read more.
Flash Poll
Rethinking Enterprise Data Defense
Rethinking Enterprise Data Defense
Frustrated with recurring intrusions and breaches, cybersecurity professionals are questioning some of the industrys conventional wisdom. Heres a look at what theyre thinking about.
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2019-19740
PUBLISHED: 2019-12-12
Octeth Oempro 4.7 allows SQL injection. The parameter CampaignID in Campaign.Get is vulnerable.
CVE-2019-19746
PUBLISHED: 2019-12-12
make_arrow in arrow.c in Xfig fig2dev 3.2.7b allows a segmentation fault and out-of-bounds write because of an integer overflow via a large arrow type.
CVE-2019-19748
PUBLISHED: 2019-12-12
The Work Time Calendar app before 4.7.1 for Jira allows XSS.
CVE-2017-18640
PUBLISHED: 2019-12-12
The Alias feature in SnakeYAML 1.18 allows entity expansion during a load operation, a related issue to CVE-2003-1564.
CVE-2019-19726
PUBLISHED: 2019-12-12
OpenBSD through 6.6 allows local users to escalate to root because a check for LD_LIBRARY_PATH in setuid programs can be defeated by setting a very small RLIMIT_DATA resource limit. When executing chpass or passwd (which are setuid root), _dl_setup_env in ld.so tries to strip LD_LIBRARY_PATH from th...