Feeds

Apache squashes 'devastating' bug under attack

Byte range vuln exposed servers to crippling DoS exploit

Choosing a cloud hosting partner with confidence

Maintainers of the open-source Apache webserver have fixed a severe weakness that attackers are exploiting to crash websites.

Flaws in Apache's HTTP daemon made it easy to crash servers using publicly available software released last week. The bugs in the way the HTTPD processed multiple web requests that involved overlapping byte ranges allowed attackers to overwhelm servers by sending them a modest amount of traffic.

An advisory on Apache's website said the bug, formally known as CVE-2011-3192 has been fixed in version 2.2.20.

“We consider this release to be the best version of Apache available, and encourage users of all prior versions to upgrade,” the advisory stated. "Active use" of the attack tool has been observed.

One of the bugs fixed in the update was specific to Apache, while a second flaw has been known since 2007, and possibly involves all webservers, an Apache bulletin said. The Internet Engineering Task Force is considering changing the underlying protocol responsible for the problem, Apache said.

Versions 1.3.x and 2.0.x through 2.0.64 contain the denial-of-service vulnerabilities. They can be triggered by a single web request that contains overlapping byte ranges for a specific page.

“The problem is that currently such requests internally explode into 100's of large fetches, all of which are kept in memory in an inefficient way,” Apache's advisory explained. “This is being addressed in two ways. By making things more efficient. And by weeding out or simplifying requests deemed too unwieldy.” ®

Beginner's guide to SSL certificates

More from The Register

next story
Russian hackers exploit 'Sandworm' bug 'to spy on NATO, EU PCs'
Fix imminent from Microsoft for Vista, Server 2008, other stuff
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?
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
Forget passwords, let's use SELFIES, says Obama's cyber tsar
Michael Daniel wants to kill passwords dead
Kill off SSL 3.0 NOW: HTTPS savaged by vicious POODLE
Pull it out ASAP, it is SWISS CHEESE
Facebook slurps 'paste sites' for STOLEN passwords, sprinkles on hash and salt
Zuck's ad empire DOESN'T see details in plain text. Phew!
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.