3-pronged Trojan Attack Threatens Web Security

[george]

3-Pronged Trojan Attack Threatens Web Security

Glieder (Win32.Glieder.AK), Fantibag (Win32.Fantibag.A) and Mitglieder (Win32.Mitglieder.CT) are not names of a modern day version of The Three Musketeers. These are Trojans engineered for a hacker attack that will infect computers and open them for use in further attacks.

Of the three, Glieder leads the initial charge. It sneaks past anti-virus protection to download and execute files from a long, hard-coded list of URLs and "plant" the infected machine with "hooks" for future use.

On Windows 2000 and Windows XP machines, it attempts to stop and disable the Internet Connection Firewall and the Security Center service (introduced with Windows XP Service Pack 2). Then the Trojan accesses the URL list to download Fantibag. The way is now paved to launch the second stage of attack.

Sulabh, a tester with MicroWorld Technologies says of Fantibag, "Now Fantibag goes about attacking the networking feature of the infected system to prevent it from communicating with anti-virus firms and denying access to the Microsoft Windows Update site. It closes your escape route by making it impossible to download an anti-virus solution and any subsequent Windows security patch to your system. Effectively, it helps Mitglieder (the third stage Trojan) open the 'backdoor' by shutting the other doors on you."

Mitglieder puts the system under complete control of the attacker by opening the 'backdoor' on a port using which the attacker can update the Trojan, to stay a step ahead of attempts to remove it, download and execute files, initiate an SMTP server to relay spam, execute files on the infected computer and download and execute files via an

URL.

According to the company, the system can then be used as a remote controlled 'soldier' (bot) in an army (botnet) of similarly compromised machines to launch attacks. Botnets thus formed can among other things, use a machine to launch Distributed Denial of Service attacks which overload servers, making them crash, to send out

spam, spread new Malware, etc.

"Such a three-pronged Trojan attack where attackers change their virus code and release viruses quickly to bypass virus signature scanners, then disable network access to deny the user link-ups to anti-virus and Microsoft Windows Update site for protection has huge significance for virus-signature based protection," said Govind Rammurthy, CEO of MicroWorld Technologies.

--cxotoday.com 2005-06-07

[george]

Details on How a Sophisticated Web Attack Works

Computer Associates describes how Bagle variant helps to turn PCs into zombies.

WASHINGTON -- A sophisticated new attack that uses three pieces of malware to turn PCs into zombies that can be sold to criminal groups has appeared on the Internet this week, security vendor Computer Associates International (CA) said Thursday.

A version of the Bagle worm downloader that CA has dubbed Glieder serves as a "beachhead" from which attackers can install more-serious malware on computers, CA said. Ultimately, through tactical coordination between Glieder and other invasive programs, infected computers can have their antivirus and firewall software disabled and can be turned into remotely controlled zombies that may then be used to mount large cyberattacks, CA said.

"This is so coordinated that it's remarkably sophisticated," said Roger Thompson, CA's director of malicious content research.

Stops Your Antivirus Tools

CA noted eight variants of Glieder released one after the other on Wednesday, "dazzling the Internet with their speed and deployment to maximize the number of compromised victims," the company said. "The whole point is to get to as many victims as fast as possible with a lightweight piece of malware."

The Glieder downloader then directs the infected computer to a Web site to download the Fantibag Trojan horse, which targets computers' networking features to prevent their systems from communicating with antivirus vendor update tools and with Microsoft's update Web site. Next, the infected computer downloads the Mitglieder Trojan horse, which disables firewalls and antivirus software and opens a back door, allowing the computer to be controlled remotely by the hackers.

"It turns computers into zombies," Thompson said of the attack. "It's all about these guys building their botnet. It's all about making money."

On Wednesday, as soon as antivirus vendors updated their programs to detect the latest version of Glieder, the attackers would modify the downloader program, resulting in an arms race, Thompson added. The use of three separate pieces of malware to attack a computer shows a new level of coordination, he said. A black market for compromised computers drives these types of zombie attacks, with criminals paying for groups of machines to use as spam relays or as sources of personal information to use in identity-theft schemes.

Others Wary

Other Internet security experts were less impressed with the Glieder attacks. Though the pairing of Glieder with Fantibag may be new, Glieder doesn't differ from older Bagle variants in being designed to work as a downloader program that can secretly install software on compromised machines, said Ken Dunham, director of malicious code at IDefense, another cybersecurity vendor.

CA warned that the new attacks may be the work of professional criminals. "There's plenty of evidence to suggest that all these things are being done by organizations," Thompson said.

Like CA, Jimmy Kuo, a research fellow with the McAfee Anti-Virus Emergency Response Team, sees a black market for zombie machines. McAfee has found evidence of criminals paying hackers to send out rounds of zombie malware attacks, he said. "The payments range from the high hundreds of dollars to the low thousands of dollars," he said.

Kuo noted that downloader attacks are becoming common and that nearly all such attacks are associated with criminal activity. In some cases, zombie machines are used to attack corporate networks by flooding them with e-mail, he said. "It's probably to the point where somewhere in the high 90 percent of all malware is associated with a money-making scheme," he said.

Dunham suggested that small-time criminals or loosely organized hacking groups, not organized crime syndicates, may be behind most such attacks.

"It is increasingly sophisticated, but not by much," Dunham said of the downloader-type attacks. "I'm not very impressed with them. I've seen much more sophisticated attacks with spyware this year than any of the downloader attacks."

Thompson and Dunham advised computer users to avoid opening any executable files they receive in e-mail. In most cases, security policies on corporate networks prohibit e-mail with executables from being delivered, but most PCs don't have the same protection, Thompson said.

--PCworld.com 2005-06-07