Microsoft IIS servers vulnerable to FTP attack

Microsoft issues security warning but doesn't yet provide a patch to fix the vulnerability

A critical flaw in the FTP component of Microsoft Internet Information Service (IIS) can allow an attacker to execute malicious commands on a server, Microsoft warned in a new security advisory.

According to a Microsoft Security Research & Defense post, if a vulnerable IIS 5.0 (Windows 2000), 5.1 (XP) or 6.0 (Server 2003) FTP service attempts to list a "long, specially-crafted directory name," a stack overflow will occur that can allow for remote code execution. IIS 7.0 (Vista, Server 2008) is not vulnerable, according to the post.

To be hit, "an FTP server would need to grant untrusted users access to log into and create that long, specially-drafted directory."

There is not yet any patch available, and Microsoft says it has seen "detailed exploit code" available online, though it hasn't yet seen any active attacks. Microsoft's post lists workarounds for the time being, including how to prevent anonymous FTP users from being able to create directories.

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.

Tags Microsoftserversiis server

Keep up with the latest tech news, reviews and previews by subscribing to the Good Gear Guide newsletter.

Erik Larkin

PC World (US online)
Show Comments

Brand Post

Most Popular Reviews

Latest Articles

Resources

PCW Evaluation Team

Tom Pope

Dynabook Portégé X30L-G

Ultimately this laptop has achieved everything I would hope for in a laptop for work, while fitting that into a form factor and weight that is remarkable.

Tom Sellers

MSI P65

This smart laptop was enjoyable to use and great to work on – creating content was super simple.

Lolita Wang

MSI GT76

It really doesn’t get more “gaming laptop” than this.

Jack Jeffries

MSI GS75

As the Maserati or BMW of laptops, it would fit perfectly in the hands of a professional needing firepower under the hood, sophistication and class on the surface, and gaming prowess (sports mode if you will) in between.

Taylor Carr

MSI PS63

The MSI PS63 is an amazing laptop and I would definitely consider buying one in the future.

Christopher Low

Brother RJ-4230B

This small mobile printer is exactly what I need for invoicing and other jobs such as sending fellow tradesman details or step-by-step instructions that I can easily print off from my phone or the Web.

Featured Content

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?