eEye Advisory - EEYEB-200505 - RealPlayer AVI Processing Overflow

["Steve Manzuik" <smanzuik () eeye com>]

RealPlayer vidplin.dll AVI Processing Heap Overflow

Release Date:
June 23, 2005

Date Reported:
May 4, 2005

Patch Development Time (In Days): 36

Severity:
High (Code Execution)

Vendor:
RealNetworks

Systems Affected:
For Microsoft Windows

RealPlayer 10.5 (6.0.12.1040-1069)
RealPlayer 10
RealOne Player v2
RealOne Player v1
RealPlayer 8
RealPlayer Enterprise

Overview:
eEye Digital Security has discovered a critical vulnerability in RealPlayer. The vulnerability allows a remote attacker 
to reliably overwrite heap memory with arbitrary data and execute arbitrary code in the context of the user who 
executed the player.

This specific flaw exists within the vidplin.dll file used by RealPlayer. By specially crafting a malformed .avi movie 
file, a direct heap overwrite is triggered, and reliable code execution is then possible.  This vulnerability can be 
trigger when a user views a webpage, or opens an .avi file via email, instant messenger, or other common file transfer 
programs.

Technical Details:
When processing AVI files RealPlayer calls upon a specific DLL, vidplin.dll, where the vulnerability lies.  Realplayer 
relies
on a strf structure value and allocates a fixed memory space of 0x428 that can be overflowed with values greater than 
the fixed buffer size causing arbitrary code to be executed.

Protection:
Retina - Network Security Scanner - has been updated to identify this vulnerability.
Blink - End-point Vulnerability Prevention - protects from this vulnerability.

Vendor Status:
RealNetworks has released a patch for this vulnerability.

http://service.real.com/help/faq/security/050623_player/EN/


Credit:
Discovery: Flashsky

Related Links:
Retina Network Security Scanner - Free 15 Day Trial http://www.eeye.com/html/Products/Retina/download.html

Blink End Point Vulnerability Prevention
http://www.eeye.com/html/Products/Blink

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