Top 10 flaws in UK e-commerce sites

Web server flaws, poor authentication mechanisms and faulty log-out facilities are the most widespread problems, with most flaws caused by relatively basic mistakes, NTA Monitor claims. Users most at risk from the flaws are those using public access terminals, where the next user is able to see personal information provided, or continue the session with full access to the account.

The most high-risk flaw regularly discovered by NTA Monitor was lack of security behind the 'front door' exposing 'root' access web server flaws, giving hackers access to critical systems once they have gained entry. The top ten most common eCommerce flaws discovered, listed in order of frequency were:

1. Lack of security behind the 'front door' exposes 'root' access web server flaws.
2. Logout facility not working: although the web site tells users they have logged out, they are actually still logged in, so anyone using the PC directly afterwards can continue the session with full access to their account.
3. Predictable authentication tokens: this makes it possible to guess valid authentication tokens to access other accounts on the system.
4. Web server allows unencrypted access to secure areas: this allows information to be sent in the clear across the Internet – and sniffed in transit.
5. Authentication token cookie is cached on disk: anyone using the PC directly afterwards can log back into the session with full access to their account.
6. Authentication fields are not obscured during entry: people looking over one's shoulder can see access details.
7. Account lockout mechanism does not work: this leaves data unprotected from malicious 'brute force' attacks.
8. No protection against keystroke loggers: this allows an attacker to log confidential information entered by the user.
9. Weak password mechanism: system allows users to choose insecure passwords, or there is no facility to change password.
10. Account enumeration possible: this enables an attacker to repeat attempts until valid user accounts are confirmed.

Roy Hills, Technical Director, NTA Monitor, said:

"Our experience shows that simple faults are worryingly common - and on a level that can be exploited even by the most unsophisticated hackers. Given that security issues are the biggest inhibitor for on-line buyers, we were surprised to find that companies are not sealing their defences more thoroughly."

The company made the following recommendations in light of its findings:

Companies should design e-commerce systems with security in mind from the outset, implementing a secure design across all layers: network, operating system, web server, and application. Done thoroughly, this will avoid much time and cost spent retro fixing problems identified later.

If outsourcing the production of an e-commerce system to a third party supplier, build in a "security quality of service" line item into the contract. Once suppliers are responsible for an area, companies will find compliance a lot easier · Get the design independently checked for security issues before buying any software or equipment.

Ensure all systems, from web server and database through to firewalls and IDS are configured securely and patched to the latest secure and stable release.

Engage regular, independent security testing prior to launch and on a regular basis throughout the year, with tests planned prior to release of major version changes.

Hills concluded, "Remember, good security is about doing the fundamentals. Our results, combined with the rapid spread of the SQL slammer worm recently, illustrate that people still fail to get the basics right."