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

4/11/2017
05:40 PM
Connect Directly
Twitter
LinkedIn
Google+
RSS
E-Mail
50%
50%

Microsoft Office Zero-Day Patched After Months of Attacks

Microsoft released a security update for a flaw in the OLE API that affects most versions of Microsoft Word.

Microsoft today patched a critcial zero-day vulnerability in Microsoft Office/WordPad that attackers had been exploiting in the wild for months.

CVE-2017-0199 is a remote code execution vulnerability in the Windows Object Linking and Embedding (OLE) application programming interface. The vulnerability already had been weaponized in attacks to distribute the Dridex banking Trojan, as a botnet payload, and in a cyber espionage campaign.

Security firm McAfee published a report on April 7 to warn users of an exploit that has been used to target users since late January. SophosLabs claims attacks actually date back to November 2016, with most occuring between March and April 2017.

There are a few reasons this bug is especially dangerous: it affects most, or all, Windows versions of Microsoft Word, and targets don't have to enable macros for exploits to be effective, explains Bryan Burns, vice president of threat research and engineering at Proofpoint.

Burns says it's a logic bug, which is harder to defend against, he says. Victims are more likely to fall for these attacks because they aren't prompted to enable macros -- something businesses teach their employees to avoid. Instead, the attacks use a dialogue box.

"They've probably been trained over the last several years not to enable macros," says Burns. "This is a different vector. Users haven't seen a dialogue box. They haven't been trained not to click on it."

The attackers attach emails containing Microsoft Word RTF (Rich Text Format) documents. Subject lines read "Scan Data" and attachments were named "Scan_123456.doc" or "Scan_123456.pdf" with "123456" replaced with random numbers, Proofpoint reports.

When launched, the exploit connects to a remote server, downloads a file containing HTML application content, and executes it as a .hta file, McAfee explains. Because .hta is executable, the attacker gains full code execution on the machine. After the malware has been installed, the exploit closes the bait Word document and displays a new one to show the victim.

The exploit uses an embedded OLE2link object in specially created documents.

"Everything is working as designed," says Burns of how the attack deceives targets. "But the way it's designed, it left a corner open so code can run when you wouldn't expect it to be running."

In the case of Dridex, attackers obtained full system control to launch the banking Trojan malware. This enabled them to grab businesses' financial credentials and intercept transactions to steal money. "In this case, it was financially motivated," says Burns of the attackers' goals. "They were trying to infect with this malware to empty out [organizations'] bank accounts."

But Burns warns that this Office flaw would allow for any type of malware to be installed. Ransomware is one example Proofpoint sees frequently distributed.

"We would expect any threat actor who is trying to attack businesses to try this technique," he cautions.

Several security firms aside from Proofpoint observed this vulnerability in the wild ahead of Microsoft's patch. Netskope's Threat Research Labs linked this zero-day to the Godzilla botnet loader. Researchers saw IPs released to the botnet loader serving payloads related to exploits for the vulnerability using malicious Word documents.

In a different scenario, FireEye spotted this flaw being used in a cyber espionage campaign targeting Russian-speaking victims since January 2017 and installing FINSPY, a tool previously associated with the "lawful intercept" company Gamma Group. FireEye in another case saw exploits installing Latentbot, a malware family used by cybercriminals for financial gain.

Now that Microsoft has issued a fix, businesses should protect themselves by patching as quickly as possible, Burns says. He also cautions organizations to be wary of these types of attacks, as email as the "dominant threat vector" hackers will use to infect businesses.

Meanwhile, today is the last day of extended support for Windows Vista. The OS will no longer receive updates or support from Microsoft. 

Related Content:

Kelly Sheridan is the Staff Editor at Dark Reading, where she focuses on cybersecurity news and analysis. She is a business technology journalist who previously reported for InformationWeek, where she covered Microsoft, and Insurance & Technology, where she covered financial ... View Full Bio

Comment  | 
Print  | 
More Insights
Comments
Oldest First  |  Newest First  |  Threaded View
technicalaccademy
50%
50%
technicalaccademy,
User Rank: Apprentice
4/12/2017 | 1:28:49 AM
Microsoft
Thanks for sharing the microsoft office zero-day.
Where Businesses Waste Endpoint Security Budgets
Kelly Sheridan, Staff Editor, Dark Reading,  7/15/2019
US Mayors Commit to Just Saying No to Ransomware
Robert Lemos, Contributing Writer,  7/16/2019
Register for Dark Reading Newsletters
White Papers
Video
Cartoon Contest
Current Issue
Building and Managing an IT Security Operations Program
As cyber threats grow, many organizations are building security operations centers (SOCs) to improve their defenses. In this Tech Digest you will learn tips on how to get the most out of a SOC in your organization - and what to do if you can't afford to build one.
Flash Poll
The State of IT Operations and Cybersecurity Operations
The State of IT Operations and Cybersecurity Operations
Your enterprise's cyber risk may depend upon the relationship between the IT team and the security team. Heres some insight on what's working and what isn't in the data center.
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2018-17210
PUBLISHED: 2019-07-20
An issue was discovered in PrinterOn Central Print Services (CPS) through 4.1.4. The core components that create and launch a print job do not perform complete verification of the session cookie that is supplied to them. As a result, an attacker with guest/pseudo-guest level permissions can bypass t...
CVE-2019-12934
PUBLISHED: 2019-07-20
An issue was discovered in the wp-code-highlightjs plugin through 0.6.2 for WordPress. wp-admin/options-general.php?page=wp-code-highlight-js allows CSRF, as demonstrated by an XSS payload in the hljs_additional_css parameter.
CVE-2019-9229
PUBLISHED: 2019-07-20
An issue was discovered on AudioCodes Mediant 500L-MSBR, 500-MBSR, M800B-MSBR and 800C-MSBR devices with firmware versions F7.20A to F7.20A.251. An internal interface exposed to the link-local address 169.254.254.253 allows attackers in the local network to access multiple quagga VTYs. Attackers can...
CVE-2019-12815
PUBLISHED: 2019-07-19
An arbitrary file copy vulnerability in mod_copy in ProFTPD up to 1.3.5b allows for remote code execution and information disclosure without authentication, a related issue to CVE-2015-3306.
CVE-2019-13569
PUBLISHED: 2019-07-19
A SQL injection vulnerability exists in the Icegram Email Subscribers & Newsletters plugin through 4.1.7 for WordPress. Successful exploitation of this vulnerability would allow a remote attacker to execute arbitrary SQL commands on the affected system.