Web server security wars: Is IIS or Apache more secure?

The facts of web servers don't necessarily match the myths when it comes to security

Continuing the theme from my previous column on the relative security of Internet Information Service (IIS) vs. Apache, I've come across more studies to support my initial conclusion.

If you remember, I was questioning the findings of a Google report that stated that IIS Web servers were twice as likely as Apache servers to be hosting malware. I wasn't refuting the data, but I was questioning the conclusion, given the fact that the report's authors calculated their statistics using server IP addresses only.

Since a single Web server can, and often does, host multiple Web sites, the published results would be skewed by any server hosting multiple Web sites. And since Apache Web servers are often used to host hundreds to thousands of active sites (and IIS is less likely to host sites on the same scale), I felt the study underreported the prevalence of malicious Apache Web sites.

I was skeptical of the data because of my own experiences. I run both IIS and Apache Web servers in my honeynet. The Apache Web server gets attacked significantly more than the IIS server does. Also, most reported hacks are against Apache Web servers. Finally, I can't think of a single massive attack against IIS servers since the Code Red worm of July 2001. Yet, Apache servers are being taken over by the thousands nearly every night. Something didn't add up.

Of course, being a full-time Microsoft employee, I wondered if my relationship was clouding my "objectivity." Because I make a living in the Windows world, was I not seeing the true malicious Web site activity accurately?

Over the last month, I've decided to track every reported Web site exploitation or malicious Web server host. With more than 3,000 data points, the number of reported malicious or compromised Apache Web sites is running 17 to 1. But it's not just my own data; take any random sampling from Zone-H's hacked Web site monitor statistics and you'll see a huge skew toward Apache servers versus IIS. Normal statistics show that somewhere around 80 to 90 percent of all malicious Web sites originate from an Apache server.

Zone-H's data has some other interesting points, such as how many single IP addresses (a single Web server, in most cases) are linked to the reported Web servers. It's not unusual to see a single exploit affecting a single IP address to result in hundreds to thousands of malicious Web sites. And yes, the vast majority of these data points are Apache.

Paul Laudanski of CastleCops fame collected supporting statistics from his own Phishing Incident Reporting and Termination Squad database for me. He said, "For PIRT reports above 500,000 (without checking their phish status): IIS = 1,302 reports, Apache = 20,104 reports. For all PIRT reports w/o confirming status: IIS = 16,744, Apache = 181,724. There are of course other Web servers I haven't checked for." That works out to be about 6 to 8 percent for IIS and 92 to 94 percent for Apache.

The overwhelming slant toward Apache cannot be explained by sheer numbers alone. Netcraft reports that in August 2007, Apache accounted for 48 percent of public-facing Web sites while IIS rose to 34 percent. So does that mean IIS is more secure than Apache?

The real answer, of course, is that both IIS and Apache, if installed as directed by the developers, are relatively secure. Most malicious Web site infections are the result of administrative mistakes and buggy applications -- not the underlying Web server software.

Open Web Application Security Project, one of the most respected organizations trying to increase Web server security, continues to report nearly the same top 10 Web site security flaws that have plagued Web sites since the beginning of the Web.

So I want to end my one-way debate of IIS vs. Apache by saying that both are fine, relatively secure platforms. Installing a secure Web server is easy; hosting secure applications on top of that secure base is the true challenge.

Join the newsletter!

Or

Sign up to gain exclusive access to email subscriptions, event invitations, competitions, giveaways, and much more.

Membership is free, and your security and privacy remain protected. View our privacy policy before signing up.

Error: Please check your email address.
Keep up with the latest tech news, reviews and previews by subscribing to the Good Gear Guide newsletter.
Roger A. Grimes

Roger A. Grimes

InfoWorld
Show Comments

Cool Tech

Toys for Boys

Family Friendly

Stocking Stuffer

SmartLens - Clip on Phone Camera Lens Set of 3

Learn more >

Christmas Gift Guide

Click for more ›

Brand Post

Most Popular Reviews

Latest Articles

Resources

PCW Evaluation Team

Aysha Strobbe

Microsoft Office 365/HP Spectre x360

Microsoft Office continues to make a student’s life that little bit easier by offering reliable, easy to use, time-saving functionality, while continuing to develop new features that further enhance what is already a formidable collection of applications

Michael Hargreaves

Microsoft Office 365/Dell XPS 15 2-in-1

I’d recommend a Dell XPS 15 2-in-1 and the new Windows 10 to anyone who needs to get serious work done (before you kick back on your couch with your favourite Netflix show.)

Maryellen Rose George

Brother PT-P750W

It’s useful for office tasks as well as pragmatic labelling of equipment and storage – just don’t get too excited and label everything in sight!

Cathy Giles

Brother MFC-L8900CDW

The Brother MFC-L8900CDW is an absolute stand out. I struggle to fault it.

Luke Hill

MSI GT75 TITAN

I need power and lots of it. As a Front End Web developer anything less just won’t cut it which is why the MSI GT75 is an outstanding laptop for me. It’s a sleek and futuristic looking, high quality, beast that has a touch of sci-fi flare about it.

Emily Tyson

MSI GE63 Raider

If you’re looking to invest in your next work horse laptop for work or home use, you can’t go wrong with the MSI GE63.

Featured Content

Product Launch Showcase

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?