Feeds

New IIS attacks (greatly) expand number of vulnerable servers

Microsoft's webserver even easier to exploit

Choosing a cloud hosting partner with confidence

Attackers have begun actively targeting an unpatched hole in Microsoft's Internet Information Services webserver using new exploit code that greatly expands the number of systems that are vulnerable to the bug.

In an updated advisory published Friday, Microsoft researchers said they are seeing "limited attacks" exploiting the vulnerability, which resides in a file transfer protocol component of IIS. Exploit code publicly released in the past 24 hours is now able to cause vulnerable servers to crash even when users don't have the ability to create their own directories.

That means the bug, for which there is no patch, is easier to exploit than previously thought. In an earlier advisory, Microsoft said attacks only worked when untrusted users had write access to directories. For the moment, Microsoft continues to say that IIS5 running on Windows 2000 appears to be the only version that is vulnerable to attacks that can remotely execute malicious code on an underlying server. But it's now clear that hackers can target every version of IIS to cause denial-of-service attacks.

Microsoft said Thursday that it planned to issue five security updates for next week's Patch Tuesday. None of the affected software listed in the limited disclosure included IIS, so users shouldn't expect a fix then. Microsoft has said only that it plans to issue a patch as soon as one is ready.

In the meantime, IIS users should follow workarounds that include turning off FTP if it's not needed (in more recent versions it's disabled by default), or at the very least, blocking FTP access to unauthenticated users.

The bug is exploited by listing directories with specially manipulated names that trigger a buffer stack overflow in the application. The new exploit code is able to cause IIS6 systems to crash, but Microsoft makes no mention those systems can be further compromised. ®

Beginner's guide to SSL certificates

More from The Register

next story
FYI: OS X Yosemite's Spotlight tells Apple EVERYTHING you're looking for
It's on by default – didn't you read the small print?
Russian hackers exploit 'Sandworm' bug 'to spy on NATO, EU PCs'
Fix imminent from Microsoft for Vista, Server 2008, other stuff
Edward who? GCHQ boss dodges Snowden topic during last speech
UK spies would rather 'walk' than do 'mass surveillance'
Microsoft pulls another dodgy patch
Redmond makes a hash of hashing add-on
'LulzSec leader Aush0k' found to be naughty boy not worthy of jail
15 months home detention leaves egg on feds' faces as they grab for more power
China is ALREADY spying on Apple iCloud users, claims watchdog
Attack harvests users' info at iPhone 6 launch
Carders punch holes through Staples
Investigation launched into East Coast stores
prev story

Whitepapers

Forging a new future with identity relationship management
Learn about ForgeRock's next generation IRM platform and how it is designed to empower CEOS's and enterprises to engage with consumers.
Cloud and hybrid-cloud data protection for VMware
Learn how quick and easy it is to configure backups and perform restores for VMware environments.
Three 1TB solid state scorchers up for grabs
Big SSDs can be expensive but think big and think free because you could be the lucky winner of one of three 1TB Samsung SSD 840 EVO drives that we’re giving away worth over £300 apiece.
Reg Reader Research: SaaS based Email and Office Productivity Tools
Read this Reg reader report which provides advice and guidance for SMBs towards the use of SaaS based email and Office productivity tools.
Security for virtualized datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.