[personal profile] mattsretechblog
As a consultant often called on by MLSs for help with VOW and IDX compliance audits as someone who is always pushing for improved information security in the real estate industry, I love that information security is featured prominently in the VOW rules, section 19.5: “A Participant’s VOW must employ reasonable efforts to monitor for, and prevent, misappropriation, ‘scraping’, and other unauthorized use of MLS listing information. A participant’s VOW shall utilize appropriate security protection, such as firewalls, as long as this requirement does not impose security obligations greater than those employed concurrently by the MLS.” The last part of that rule is also reflected in optional IDX rule section 18.3.14. Auditing these rules has allowed me to help many brokers improve their VOW and IDX security and reduce the risk of an information security incident.

I’ve already written about guidelines for anti-scraping and monitoring and, although anti-scraping is a constantly evolving challenge, that article provides at least a baseline for evaluating VOW rule compliance.

But, what else should MLSs be looking for when evaluating VOW and IDX security?

First, as specifically mentioned in the rule, appropriate firewall protection must be established. When I audit a VOW, I look to make sure that there are only a few specific network ports open on the server – 80 and 443 as needed for the web server to function, and ports needed to provide a secure method of server administration, such port 22 – or 989 and 990. If ports like 21 and 3389 are open and actually used to administer the website, it should be a big compliance red flag because they are common security incident causes – and issues I see the majority of the time when auditing a VOW or IDX site.

Second, you want to verify that all the web server software is up to date and properly configured. That means checking the web server (IIS, Apache, etc.) version, the operating system version (when possible) and the platform (.NET, JSP, ColdFusion, WordPress, etc.) version, making sure that those are the most current versions or that newer versions don’t have fixes for significant security vulnerabilities. You might think that keeping systems patched would be second nature for a technology provider, but in my experience, it seems not to be the case.

Third, you want to evaluate any externally obvious security misconfigurations of the server and platform. Every server and platform has its own security configuration guidelines and it’s reasonable to expect that obviously poor configurations should not be visible to an external evaluator.

Fourth, and probably the most complicated part of evaluating VOW security, you want to evaluate application security – at least the OWASP Top 10 Vulnerabilities: Injection, Cross-Site Scripting (XSS), Broken Authentication and Session Management, Insecure Direct Object References, Cross-Site Request Forgery, Security Misconfiguration, Insecure Cryptographic Storage, Failure to Restrict URL Access, Insufficient Transport Layer Protection, and Unvalidated Redirects and Forwards. I usually evaluate Information Leakage and Improper Error Handling as well. Some of these items can’t be easily validated externally (i.e. Insecure Cryptographic Storage) though I’m always glad to hear that a web developer has encrypted the passwords and so cannot technically be compliant for VOW rule 19.3b. (“The Participant must at all times maintain a record of the name, email address, user name, and current password of each registrant.”). I’ve seen every one of these OWASP vulnerabilities while auditing VOWs and many times there are half a dozen issues on a single VOW.

If you’re a staff person at an MLS and a lot of the preceding read like gobbledy-gook to you or you don’t know how to audit security, you may want someone like me auditing VOWs and IDX sites for you, or at least auditing the security and anti-scraping related portions. It has been a blessing for the industry that the VOW and IDX rules give MLSs the opportunity to ensure that at least some reasonable security best practices are in place for VOW sites. I’ve had brokers tell me they were actually grateful someone was keeping an eye on their technology provider in this area, since they lacked the capacity to do so themselves and just figured that all appropriate measures had been taken.

Please keep in mind that website security is the smallest portion of overall brokerage security. Taking appropriate steps in terms of policies and contracts, physical security, account management and password controls, internal networking and computing, mobile device security, and internal web applications are all important. The NAR sponsored security workshops and security articles and blogs that I write, and which many MLSs and Associations reprint, are helping me reach some brokers and agents – but it’s a very difficult task to try to improve information security in this industry and I hope that I can count on my readers to act as security allies and spread the word.
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mattsretechblog: matt cohen (Default)
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