With all the talk about hackers launching attacks from legitimate Websites, you'd think that the major security vendors' sites, at least, would be vulnerability-free.

Not so, according to a report issued yesterday by a security watchdog site.

The site, XSSed, states that it has verified some 30 cross-site scripting vulnerabilities spread across the Websites of three of the industry's best-known security vendors: McAfee, Symantec, and VeriSign. The vulnerabilities could make it possible for attackers to launch phishing campaigns from these sites or even distribute malware to the companies' customers, according to XSSed.

Recent studies have shown that Web-based attacks are increasingly being launched from trusted, legitimate sites, rather than from hastily created sites and servers built by the attackers. By exploiting vulnerabilities in legitimate sites, the attacker gains credibility for phishing or malware links and bypass security tools that blacklist known phishing sites. (See 68% of Malware Now Found on Legitimate Sites and 'Hack-and-Pier' Phishing on the Rise.)

The new XSSed report shows that the big security vendors' sites are no exception to this trend, said Kevin Fernandez, one of the founders of XSSed. "It shows that any company can be infected with XSS," he says. In fact, some attackers have specifically targeted their vulnerability searches on sites such as McAfee, Symantec, and VeriSign, looking on them as a particular challenge, Fernandez says.

"It is unfortunate that many Websites tend to suffer from relatively simple vulnerabilities. It’s worse, though, that the same security vendors who preach security are the ones who often need just as much help as everyone else," says Robert Hansen (aka RSnake), CEO of SecTheory, a security consulting firm. "It just lends credence to the belief that knowledge of the problems doesn’t make you immune to them, which is why education doesn’t appear to be working."

This isn't the first time that XSS vulnerabilities have been exposed on sites such as McAfee's and Symantec's, notes Jeremiah Grossman, CTO of WhiteHat Security. Back in January, XSSed reported that some 60 sites that had received the "hacker safe" label from McAfee's ScanAlert service were vulnerable to XSS attacks. (See Many 'Hacker Safe' Websites Found Vulnerable.)

At the time, Joseph Pierini, director of enterprise services for the ScanAlert "Hacker Safe" program, maintained that XSS vulnerabilities couldn't be used to hack a server. "You may be able to do other things with it," he said. "You may be able to do things that affect the end-user or the client. But the customer data protected with the server, in the database, is not going to be compromised by a cross-site scripting attack, not directly."

"XSS vulnerabilities do present a serious risk; however to date their real-world use has been limited," said Oliver Friedrichs, director of Symantec Security Response, following the XSSed report in January. "XSS vulnerabilities can result in the theft of session cookies, Web site login credentials, and exploitation of trust. XSS vulnerabilities are site-specific, and therefore their lifecycle is limited; they become extinct once they are discovered and repaired by the Website owners."

But both Fernandez and Grossman noted that there have been a number of recent attacks that exploited XSS vulnerabilities in major Websites, including MySpace, Paypal, and major Italian banks.

"Should we be worried? About XSS, yes, but not because these particular security vendors have XSS on their Websites," Grossman says. "Symantec and McAfee really don't specialize in Web application security -- they focus more attention on anti-virus and anti-malware.

"The main worry should be around the more popular and e-commerce driven Websites, like banks, credit unions, social networks, and storefronts," Grossman says. "That is where businesses and users have the most to lose -- and where the real bad guys are focusing their attention."

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