A server belonging to the Massachusetts Institute of Technology was commandeered by hackers who used it to launch attacks against other websites as part of a larger drive-by download campaign, according to antivirus vendor BitDefender.
"One MIT server (CSH-2.MIT.EDU) hosts a malicious script actively used by cyber-crooks to scan the web for vulnerable websites," the BitDefender researchers who spotted the attack said in a blog.
The rogue script hosted on the MIT server searched for vulnerable installations of phpMyAdmin, a popular Web-based database administration tool.
When the script finds a server with phpMyAdmin version 2.5.6 through 2.8.2, it exploits a vulnerability in the application and injects malicious code into the underlying databases.
This attack campaign started in June and resulted in over 100,000 compromised websites so far, said BitDefender spokeswoman Loredana Botezatu.
The company's researchers believe that the attacks are related to the Blackhole Exploit Pack, one of the most popular drive-by download toolkits currently used by cybercriminals.
Users visiting websites compromised in this campaign will be redirected to exploits for vulnerabilities in Java and other browser plug-ins, which try to install malware on their computers.
BitDefender said that it tried to alert MIT about the security breach on their server, but received no reply. The institution did not answer requests for comment sent by IDG.
As far as the BitDefender researchers could tell, the server is still online, but no longer attacking websites. Hackers prefer to abuse servers from large organizations because requests sent from them are more likely to pass network filters, according to the researchers.
The fact that these servers have considerable resources and bandwidth at their disposal is also appealing to cybercriminals and could cause problems for less powerful systems that find themselves attacked. The denial-of-service effect on the smaller systems can be easily mitigated by filtering traffic from the offending IP addresses. However, most of the time hackers don't care if that happens because they use a hit-and-run approach.
"Even if they are likely to be spotted and terminated, by the time the infected server is taken offline, it has yielded more victims than a regular bot-infected PC," the BitDefender spokeswoman said.
Webmasters are advised to remove old applications from their servers or keep them updated even if they are only rarely used. They should also review the server logs regularly for unusual requests that could be an indication of an attack in progress.
Drive-by downloads toolkits like Blackhole continue to be popular with cybercriminals because a large number of users do a poor job of keeping their operating systems, browsers and other Internet-facing software up to date.