TippingPoint Zero Day Initiative

RealNetworks RealPlayer Malformed AAC File Parsing Remote Code Execution Vulnerability

ZDI-11-332: November 28th, 2011


CVSS Score

Affected Vendors

Affected Products

Vulnerability Details

This vulnerability allows remote attackers to execute arbitrary code on vulnerable installations of RealNetworks Realplayer. AUser 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 AAC files. When parsing an AAC file, Realplayer will create buffers based on the type of Channel it finds in the first frame. When the AAC starts with a Single channel in the first frame, and then changes to a channel pair in the following frame, Realplayer fails to update the buffer size for the channel data. The buffer overwrite that follows could result in remote code execution under the context of the current user.

Vendor Response

RealNetworks has issued an update to correct this vulnerability. More details can be found at:

Disclosure Timeline

    2011-07-20 - Vulnerability reported to vendor
    2011-11-28 - Coordinated public release of advisory


This vulnerability was discovered by:
    Luigi Auriemma