RealNetwork RealPlayer MPG Width Integer Underflow Remote Code Execution VulnerabilityZDI-11-331: November 28th, 2011
TippingPoint™ IPS Customer ProtectionTippingPoint IPS customers are protected against this vulnerability by Digital Vaccine protection filter ID 11474. For further product information on the TippingPoint IPS:
This vulnerability allows remote attackers to execute arbitrary code on vulnerable installations of Realplayer. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file.
The specific flaw exists within the way RealPlayer handles MPEG files. Realplayer parses the mpg file by doing a do while loop where it uses the width of the movie for the loop condition. However, it will substracts 1 from the width for every iteration of the loop and then compare it to 0. If the width of the movie was zero at the beginning the loop will run 0xFFFFFFFF times. This results in a memory corruption that can lead to remote code execution under the context of the current user.
Vendor ResponseRealNetworks has issued an update to correct this vulnerability. More details can be found at:
2011-08-22 - Vulnerability reported to vendor
2011-11-28 - Coordinated public release of advisory
CreditThis vulnerability was discovered by: