ZDI-09-050: Sun Java Web Start JPEG Header Parsing Integer Overflow
Vulnerability
http://www.zerodayinitiative.com/advisories/ZDI-09-050
August 5, 2009

-- Affected Vendors:
Sun Microsystems

-- Affected Products:
Sun Microsystems Java Runtime

-- Vulnerability Details:
This vulnerability allows remote attackers to execute arbitrary code on
vulnerable installations of Sun Java Web Start. User interaction is
required to exploit this vulnerability in that the target must visit a
malicious page.

The specific flaw exists within the code that handles loading a custom
JPEG splash screen for a WebStart application. While handling certain
parts of the splash screen, javaws.exe makes an improper calculation
which is later used for an allocation. Later during decompression, Java
Web Start will write data into this mis-allocated buffer resulting in a
heap-based buffer overflow and eventual code execution under the context
of the current user.

-- Vendor Response:
Sun Microsystems has issued an update to correct this vulnerability. More
details can be found at:

http://sunsolve.sun.com/search/document.do?assetkey=1-66-263428-1

-- Disclosure Timeline:
2009-03-26 - Vulnerability reported to vendor
2009-08-05 - Coordinated public release of advisory

-- Credit:
This vulnerability was discovered by:
    * Anonymous

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