Hackers Reveal Vulnerable Websites

Hackers on a popular hacking message board have begun posting cross-site scripting (XSS) vulnerabilities they've found on public Websites, including those of Dell, HP, MySpace, and Photobucket, as well as security companies F5 and Acunetix.

"I think they're just looking on Website after Website and finding holes and posting to the message board," says Jeremiah Grossman, CTO for White Hat Security, who has been watching a heavy volume of XSS vulnerability posts on the "Sla.ckers" message board in the past few days. Grossman says it's unusual to see such a volume of vulnerabilities posted so publicly, plus these are "real, live Websites," he notes.

They're posting proof-of-concept code that shows how to exploit the XSS vulnerabilities, but so far there's been no sign of anything malicious, Grossman says. XSS has now surpassed buffer overflow as the number one weakness in software that attackers are exploiting. (See Cross-Site Scripting: Attackers' New Favorite Flaw.)

Grossman says the vulnerabilities being posted on the Sla.cker message board -- a board that's frequented by hackers, developers, and researchers -- don't indicate a unified or targeted effort. The XSS activity on the message boards shows how XSS flaws are getting more attention. "Now everyone wants to see where they can find them," he says. "For the moment, it doesn't look like the real bad guys are trying to exploit these and do damage.

"But if these guys are experimenting and finding these issues en masse, you can only imagine what the real bad guys are doing." Grossman says he tries to contact potential victim companies when he finds such posts.

The bottom line is many organizations have large numbers of Websites and have to find XSS and other vulnerabilities in their Web server platforms and Web apps and fix them. Randy Abrams, director of technical education for ESET, says many Website developers don't get the proper training on security practices. "They are able to put up a slick Website that looks really good, but they don't have the training to secure the sites and make sure it's not vulnerable to different types of attacks," he says.

Grossman says the companies' whose sites are posted on the message board should immediately fix the XSS vulnerabilities and check their logs to be sure nothing got in. And don't click on the links listed by the hackers.

— Kelly Jackson Higgins, Senior Editor, Dark Reading