Feeds

Scramble to fix Skype security bug

Hanging on the telephone

Choosing a cloud hosting partner with confidence

Security researchers have identified two groups of potentially serious security vulnerabilities involving Skype, the popular VoIP client software. Both create a means for hackers to run hostile code on systems running vulnerable versions of Skype. Skype has issued patches for the "critical" security bugs.

In the first case, a security bug in the Skype for Windows means the software can be crashed and forced to execute arbitrary code through a buffer overflow when presented with malformed URLs in the Skype-specific URI format callto:// and skype://. Skype can also be made to execute arbitrary code via the importation of a maliciously formated VCARD (an electronic business card format).

A second security vulnerability is not restricted to Windows PCs and hits Skype across all supported platforms. Here a heap-based buffer overflow security is the culprit but the upshot is the same as the Windows specific bug - hackers might be able to take over vulnerable systems, at least in theory. At the time of writing, neither of the security bugs is subject to either publicly available exploits or malicious code. Nonetheless users are urged to upgrade to Skype for Windows release 1.4.*.84, Skype for Mac OS X 1.3.*.17 or Skype for Linux 1.2.*.18 or later to guard against attack. No patch for Skype for Pocket PC has been released.

The vulnerabilities were discovered by Pentest and EADS Corporate Research Center. A bulletin from Secunia provides links to relevant advisories and patches. Advisories from Skype can be found here and here.

The scope - and cross-platform reach - of the vulnerabilities has security researchers worried. "Skype's ubiquity and the closed nature of their protocol means that all clients are based on the same code – Windows, Linux, business and home users all share the same, equally vulnerable client, a fecund breeding ground for worms and other malicious code," said Tom Newton, product manager for firewall vendor SmoothWall. "Skype's ease of use is partially facilitated by the port-agile firewall-dodging protocol used – this poses further danger to unsuspecting administrators who may not realise the scope of VoIP activity on their network."

In a statement, Skype said it reacted swiftly to reports of security vulnerabilities in its communications software with the release of software updates. "The updates were needed in order to fix two software problems, one of which can render a user vulnerable to a malicious attack if the user is duped into following web hyperlinks that are specially crafted to cause unwanted software to run."

"Skype proactively discloses and rates security issues when they arise so that its customers have the latest information about its software. In addition, Skype participates as a member in the international Forum of Incident Response and Security Teams, a global body that allows for rapid interchange of information among software vendors, government, business and network operators," it added. ®

Internet Security Threat Report 2014

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
NOT OK GOOGLE: Android images can conceal code
It's been fixed, but hordes won't have applied the upgrade
'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
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.
Why and how to choose the right cloud vendor
The benefits of cloud-based storage in your processes. Eliminate onsite, disk-based backup and archiving in favor of cloud-based data protection.
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.