Security on Social Networks Takes Efforts by All Sides

The popularity of social networking sites such as Facebook, LinkedIn and MySpace means they will increasingly become a target for attackers. Securing them takes a combination of efforts by users, enterprises and the social networks themselves.

When reports surfaced this month that a new variant of the Koobface worm was slithering its way across Facebook, it became another entry into the book of malware targeting social networking sites.

Security vendors expect more of the same in 2009, with attackers adding a touch of social engineering to infect users of sites such as MySpace and Facebook. For enterprises, users and even the social networking sites themselves, it may be time to take a firmer stance on security.

"The best advice for users is to avoid promiscuous -friending,'" advised Mary Landesman, senior security researcher at ScanSafe. "There's a real trend among members of social networking sites to friend as many folks as possible, even if they don't actually know them. This virtual popularity contest provides ripe opportunities for would-be attackers, who simply have to send some friend requests, get them accepted (and) then manually start the worm's initial spread."

This was borne out at the Black Hat conference in Las Vegas earlier this year when security researchers Nathan Hamiel and Shawn Moyer created a phony LinkedIn page and were able to convince more than 50 people to join them as -connections' in a single day.

The very nature of social networking sites, which people join purposely to share information, makes such ploys easy. Still, applying well-known best practices for Web surfing can make a difference.

"Regardless of whether you know - or think you know - the sender, never click on links received unexpectedly," Landesman continued. "And if you do click a link that then requests you install something, do not install it. If you have reason to believe a legitimate update is required, visit that vendor's Web site directly and update from there."

Enterprises have a choice to make - do they allow social networking sites, which can be either an important part of doing business or a potential distraction for employees, or prohibit them. Paul Roberts, an analyst with The 451 Group, said an enterprise's approach to social networking depends on a number of factors, from the nature of the business to which employees are using the sites.

"I think that increasingly companies are going to consider what you do online, on these social networking sites, to be their purview, particularly if there is a clear connection (on the site) between you and the company," he said.

For those businesses that decide to allow social networking sites in the workplace, it is important to set clear standards for use. Policies can go from general to granular, covering everything from privacy settings on user accounts to what business-related material can be posted.

The user interaction on social networking sites can be a double-edged sword from a security perspective, and several security researchers said social networks should scan content uploaded by users prior to making it available to the world on their servers.

"Content scanning for malware prior to publication will significantly help to minimize such malware distribution method that is becoming popular on these sites worldwide," opined Yuval Ben-Itzhak, CTO of Finjan.

One of the inherent security issues for sites such as Facebook and MySpace is the presence of third-party applications. If developers aren't creating secure code, or worse yet, are intentionally building malicious applications, users could be at risk. To help address this, Facebook requires developers agree to comply with technical and policy guidelines banning malicious activity before they can build on the site's platforms.

To bolster its defenses, Facebook uses automated systems to perform statistical anomaly analysis of the activity on the site. Facebook also monitors user reports of suspicious messages or other activity to flag issues for investigation. If the automated system finds activity that looks out of place, it may block suspicious content or flag it for the company's security team.

"In some cases, the bad URLs will use a good domain to hide their activity - tinyURL, for example," said Barry Schnitt, senior manager of corporate communications at Facebook. "In those cases or if the content is suspicious but not confirmed to be malicious, we'll require users to solve a CAPTCHA before posting these URLs."

"We'll then run two scripts across Facebook," he continued. "The first will force logouts of infected accounts, reset passwords and send e-mails to the users notifying them and providing information to resolve problem. The second script will do a bulk delete of the content... that is intended to infect other users."

"Managing security is to some extent an arms race," Schnitt noted, "and we're committed to continuing to invest in technical, investigative and user support resources to stay ahead of the threats."