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.

Attacks/Breaches

8/29/2011
04:10 PM
Connect Directly
Google+
Twitter
RSS
E-Mail
50%
50%

New Windows Worm Wriggling Through Networks

'Morto' targets weak passwords, usernames and spreads via the Remote Desktop Protocol

A retro worm attack is underway that takes the unusual spin of employing the Remote Desktop Protocol (RDP) in Windows' remote desktop connection feature as its attack vector.

Researchers from Microsoft, F-Secure, eEye Digital Security, and other organizations say the so-called Morto worm infects Windows workstations and Windows servers. It spreads by uploading a Windows DLL file to a targeted machine. The worm looks for weak administrator passwords in Remote Desktop on an organization's network -- everything from "12345" to "admin" and "password."

Researchers say the attack could be used for various purposes, including distributed denial-of-service (DDoS) attacks against targeted organizations. "The remote control feature allows bot-like control of the infected machines and they can be used for basically any purpose," says Mikko Hypponen, chief research officer of F-Secure Lab.

Microsoft's Malware Protection Center (MMPC), which sounded the alarm about the worm over the weekend, on Friday added detection for Worm:Win32/Morto.A. The relative number of infections isn't as high as with other malware families, but the worm generates "noticeable" amounts of traffic, according to Microsoft.

As of Saturday, there were only a few thousand computers infected with Morto, according to Microsoft's data. That's in contrast to nearly 30,000 infected with the Sality family of malware, and more than 10,000 with IRCbot malware, according to Microsoft.

"Based on telemetry through the remainder of Sunday, August 28, we are continuing to see low detections in comparison to established malware families as mentioned in the MMPC blog," says Pete Voss, senior response communication manager for Microsoft Trustworthy Computing. "It’s important to remember that this malware does not exploit a vulnerability in Remote Desktop Protocol, but instead relies on weak passwords ... We encourage people to use strong passwords to help protect their systems."

Researchers for the Contagio blog note that Morto generates significant traffic, and appears to have ties to China and Hong Kong. "I can add that it runs what it looks like a quick DoS test against one Google IP. In addition, it creates a lot of traffic: RDP scans, downloads, receiving commands, and interesting DNS queries for command and control servers," says a post by "Mila" today. "Judging by the domain owners of CC servers (China) and their location (Hong Kong), I would say it is likely it be cybercrimeware originating in erm...Asia. I don't know how difficult it is for a foreigner to register domains with Jiangsu Bangning Science & technology Co. Ltd.in China. One of the domains existed for a few years and changed several Chinese registrars and hosting companies. Like in Russia, DDoS attack crimes are very common in China."

Once Morto compromises one system, it connects to a command and control server to download information and to update its malware. "It also terminates processes for locally running security applications in order to ensure its activity continues uninterrupted. Affected users should note that a reboot may be required in order to complete the cleaning process," Hil Gradascevic of MMPC Melbourne blogged yesterday.

Marc Maiffret, CTO of eEye, says there are some common-sense ways to prevent being hit by "this silly worm."

Among his recommendations: RDP access from the Internet should use VPN authentication. "You need to always be minimizing your attack surface, and a great example of that is not allowing RDP to be probed by any joe hacker with a port scanner," Maiffret blogged today. Stop using weak passwords, he says, and try to throw off the worm and other attacks by moving your network services to different, non-standard ports. "This can be done for RDP through a simple registry key change which makes it easy to standardize across your entire network if you so choose," he says.

Meanwhile, Microsoft says Morto also tries to connect to targeted host systems if it can't get to an admin account, using easy-to-guess usernames like "admin" and "guest," for example.

Morto is also known as Trojan horse Generic24.OJQ (AVG); Trojan.DownLoader4.48720 (Dr.Web) ; Win-Trojan/Helpagent.7184 (AhnLab); Troj/Agent-TEE (Sophos); and Backdoor:Win32/Morto.A (Microsoft).

Have a comment on this story? Please click "Add Your Comment" below. If you'd like to contact Dark Reading's editors directly, send us a message.

Kelly Jackson Higgins is the Executive Editor of Dark Reading. She is an award-winning veteran technology and business journalist with more than two decades of experience in reporting and editing for various publications, including Network Computing, Secure Enterprise ... View Full Bio

Comment  | 
Print  | 
More Insights
Comments
Newest First  |  Oldest First  |  Threaded View
How Attackers Could Use Azure Apps to Sneak into Microsoft 365
Kelly Sheridan, Staff Editor, Dark Reading,  3/24/2020
Malicious USB Drive Hides Behind Gift Card Lure
Dark Reading Staff 3/27/2020
Register for Dark Reading Newsletters
White Papers
Video
Cartoon Contest
Write a Caption, Win a Starbucks Card! Click Here
Latest Comment: This comment is waiting for review by our moderators.
Current Issue
6 Emerging Cyber Threats That Enterprises Face in 2020
This Tech Digest gives an in-depth look at six emerging cyber threats that enterprises could face in 2020. Download your copy today!
Flash Poll
State of Cybersecurity Incident Response
State of Cybersecurity Incident Response
Data breaches and regulations have forced organizations to pay closer attention to the security incident response function. However, security leaders may be overestimating their ability to detect and respond to security incidents. Read this report to find out more.
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2020-10940
PUBLISHED: 2020-03-27
Local Privilege Escalation can occur in PHOENIX CONTACT PORTICO SERVER through 3.0.7 when installed to run as a service.
CVE-2020-10939
PUBLISHED: 2020-03-27
Insecure, default path permissions in PHOENIX CONTACT PC WORX SRT through 1.14 allow for local privilege escalation.
CVE-2020-6095
PUBLISHED: 2020-03-27
An exploitable denial of service vulnerability exists in the GstRTSPAuth functionality of GStreamer/gst-rtsp-server 1.14.5. A specially crafted RTSP setup request can cause a null pointer deference resulting in denial-of-service. An attacker can send a malicious packet to trigger this vulnerability.
CVE-2020-10817
PUBLISHED: 2020-03-27
The custom-searchable-data-entry-system (aka Custom Searchable Data Entry System) plugin through 1.7.1 for WordPress allows SQL Injection. NOTE: this product is discontinued.
CVE-2020-10952
PUBLISHED: 2020-03-27
GitLab EE/CE 8.11 through 12.9.1 allows blocked users to pull/push docker images.