Feeds

Exploit code targets unpatched Windows flaw

Persistence of memory

Seven Steps to Software Security

Hackers have developed proof-of-concept code that attempts to take advantage of an unpatched Windows vulnerability to crash systems, Microsoft warned yesterday. Fortunately the risk of attack is low.

The experimental code shows it's possible to knock over machines running Windows XP SP1 and Windows 2000 SP4 in certain configurations by taking advantage of flaws in Windows memory allocation functions. This vulnerability manifests itself when a malformed request is made to the UPnP service in the data section of a call to the GetDeviceList function. In handling this request, memory consumption on vulnerable Windows boxes increase to the point where the system becomes unresponsive. Repeated requests can therefore be used to mount denial of service attacks.

Attacks on Windows XP SP1 would rely on having user authentication, reducing the scope for mischief by remote hackers. Microsoft users running Windows XP Service Pack 2, Windows Server 2003 and Windows Server 2003 Service Pack 1 are not affected by the vulnerability. Win 2000 shops are most at risk but providing systems are properly firewalled then attacks should fail.

Irresponsible disclosure?

Normally the arrival of proof-of-concept illustrates weaknesses that might subsequently by used by hackers for more malign purposes. In this case, however, the attack approach is not especially successful in slowing down systems to a crawl much less as a means to infect vulnerable machines with hostile code. This is a denial of service only risk and the real interest (except to people interested in revisiting the long-running debate about the responsible disclosure of security bugs) is that it is based on an unpatched vulnerability.

Winny Thomas of Nevis Labs in India, the security researcher who developed the proof-of-concept code, readily concedes the Windows RPC memory allocation remote denial of service exploit he highlights is only a moderate risk. Microsoft is yet to develop a security fix. It criticises Thomas of publicising details of the flaw through FrSIRT, a full disclosure web site, instead of submitting it to Microsoft directly first. ®

Mobile application security vulnerability report

More from The Register

next story
Yorkshire cops fail to grasp principle behind BT Fon Wi-Fi network
'Prevent people that are passing by to hook up to your network', pleads plod
HIDDEN packet sniffer spy tech in MILLIONS of iPhones, iPads – expert
Don't panic though – Apple's backdoor is not wide open to all, guru tells us
NEW, SINISTER web tracking tech fingerprints your computer by making it draw
Have you been on YouPorn lately, perhaps? White House website?
LibreSSL RNG bug fix: What's all the forking fuss about, ask devs
Blow to bit-spitter 'tis but a flesh wound, claim team
Attackers raid SWISS BANKS with DNS and malware bombs
'Retefe' trojan uses clever spin on old attacks to grant total control of bank accounts
Manic malware Mayhem spreads through Linux, FreeBSD web servers
And how Google could cripple infection rate in a second
Mozilla fixes CRITICAL security holes in Firefox, urges v31 upgrade
Misc memory hazards 'could be exploited' - and guess what, one's a Javascript vuln
Don't look, Snowden: Security biz chases Tails with zero-day flaws alert
Exodus vows not to sell secrets of whistleblower's favorite OS
prev story

Whitepapers

Designing a Defense for Mobile Applications
Learn about the various considerations for defending mobile applications - from the application architecture itself to the myriad testing technologies.
How modern custom applications can spur business growth
Learn how to create, deploy and manage custom applications without consuming or expanding the need for scarce, expensive IT resources.
Reducing security risks from open source software
Follow a few strategies and your organization can gain the full benefits of open source and the cloud without compromising the security of your applications.
Boost IT visibility and business value
How building a great service catalog relieves pressure points and demonstrates the value of IT service management.
Consolidation: the foundation for IT and business transformation
In this whitepaper learn how effective consolidation of IT and business resources can enable multiple, meaningful business benefits.