From Zone H.org:
08/13/2004

Date: Aug 12 2004

Impact: Execution of arbitrary code via network, User access via network

Advisory: eEye Digital Security

Description: A vulnerability was reported in RealPlayer. A remote user can execute arbitrary code.

eEye Digital Security reported that a remote user can cause arbitrary code to be executed on the target user's system with the privileges of the target user. The specific nature of the vulnerability was not reported.

Default installations are affected, the report said.

The vendor was notified on August 9, 2004.

The original notice is available at:

http://www.eeye.com/html/research/up.../20040811.html

Impact: A remote user can execute arbitrary code on the target system with the privileges of the target user.

Solution: No solution was available at the time of this entry.

Vendor URL: www.real.com/

Cause: Not specified
And here's some more information.