Web Services Security: Trouble in Transit

Web services put more of your company's data into the ether, offering more chances for someone to snatch it.

August 16, 2004 (Computerworld)

A transport company's trucks are scheduled for bogus pickups. A financial services firm's investment data is given away for free. A health insurance provider's private patient data is exposed. These are the disastrous situations that can occur when Web services data is nefariously snatched midstream.

The shareable design of Web services, which gives companies the benefit of easily exchanging data and applications with business partners, also makes them vulnerable to security breaches. Hackers have found ways to tweak the XML code used to tag the data so activity that's actually an attack appears to be valid.

"XML standards are being constructed in bits and pieces, and that's the kind of event that leads to holes that someone didn't think about," says Randy Heffner, an analyst at Forrester Research Inc.

According to experts, hackers have three methods for breaching Web services and XML security: identity-based attacks, in which a hacker poses as an authorized user to gain access to Web services; malicious-content attacks, in which an intruder forces a Web server to perform an unauthorized activity; and operational attacks, in which a hacker manipulates an XML message to tie up server resources. But although the methods are known, safeguarding Web services is difficult because multiple elements must be locked down -- the servers, the messages and the applications. Companies must first secure their Web servers and then decide which business partners and employees will have access to them, how they'll connect to them and which authentication method to use.

No Small Task
Defense manufacturer Northrop Grumman Corp. experienced that difficulty firsthand. Web services are a major component of its Myngc.com portal, which was expected to take about six months to complete. But because of security requirements such as user authentication, the project took three times as long, says Thomas Shelman, vice president and CIO.

The portal gives Los Angeles-based Northrop Grumman a way to efficiently share ordering and billing data with customers and partners, he says. But while Myngc.com provides greater data access to more people, it also creates vulnerabilities because many users outside the organization have access to business applications.

"[The portal] was a significantly larger task than we thought going into it," Shelman says. "I know a lot of companies that are implementing the same sort of thing, and they don't address the security aspects. They're leaving themselves very vulnerable."

"The need for security goes up exponentially as you're trying to expose applications to your business partners," adds Raphael Holder, vice president of shared services operations at Northrop Grumman. He says the company first grappled with how to provide secure remote access to Web services applications for internal employees and ensure that all users entering the portal were authenticated.

"It sounds simplistic, but we're providing more capability here than we have through remote access in general," says Holder. "We're providing access to portlets that touch business data, not just e-mail."

To secure its data, Northrop Grumman deployed a public-key infrastructure system from RSA Security Inc., issuing tokens to all employees authorized to access the portal. Tokens will also be issued to appropriate partners and customers for different levels of access, Holder says. Eventually, the portal will have more than 120,000 users.

Even with the current technology in place, Holder acknowledges that there are security risks with Web services. "We will have to manage [the portal] very closely, and access will be done on a business-case basis with those partners we highly trust," he says.

Exploring the Options
As it explores Web services, Wyndham International Inc., a Dallas-based hospitality company, is also looking closely at how it can provide tight security. Wyndham's research shows that it endured more than 9.5 million attempts at information security breaches from May 2003 through May 2004. They included hacker attacks, Web site defacements and viruses.

"Obviously, security is a huge concern of ours," says Mark Hedley, the company's senior vice president and chief technology officer. He says Wyndham plans to get Web services from its provider of central reservation systems technology, Micros Systems Inc., using industry-standard protocols. Hedley says his company expects Web services to make it easier for customers to obtain reservations and for Wyndham to share data with suppliers. Wyndham plans to finalize its security plan and implement Web services by the first quarter of 2005.

Heffner notes that there are several ways to approach Web services security. One of the most common is to secure applications at the transport layer, with two-way Secure Sockets Layer connections or a dedicated virtual private network link. SSL can include mutual authentication such as client certificates. Another option, which Heffner says is more suitable for connecting with multiple partners, is to use XML security gateways. These are network appliances that protect XML and Web services from attacks. They feature XML encryption, digital signatures, access control and other capabilities. Many in the industry expect that new standards will also help bolster security.

Heffner says Web services security is improving because of new standards and products. "XML security gateways provide better solutions for attack protection than existed a year ago," he says.

Security concerns shouldn't get in the way of Web services implementations, says Heffner. "You may have to spend more now on security than in three years," when more safeguards are built into Web services products, he says. "The bottom line is, if there's business value for Web services now, you shouldn't be holding it up."

Violino is a freelance writer in Massapequa Park, N.Y. Contact him at bviolino@optonline.net.