ZDI-07-005: Sun Microsystems Java GIF File Parsing Memory Corruption
            Vulnerability
http://www.zerodayinitiative.com/advisories/ZDI-07-005.html
January 16, 2007

-- CVE ID:
CVE-2007-0243

-- Affected Vendor:
Sun Microsystems

-- Affected Products:
JDK and JRE 5.0 Update 9 and earlier (all platforms)
SDK and JRE 1.4.2_12 and earlier (all platforms)
SDK and JRE 1.3.1_18 and earlier (all platforms)

-- TippingPoint(TM) IPS Customer Protection:
TippingPoint IPS customers have been protected against this
vulnerability since December 18, 2006 by Digital Vaccine protection
filter ID 4325. For further product information on the TippingPoint IPS:

    http://www.tippingpoint.com 

-- Vulnerability Details:
This vulnerability allows attackers to execute arbitrary code on
vulnerable installations of Sun Microsystems Java Virtual Machine
(JVM). User interaction is required to exploit this vulnerability in
that the target must visit a malicious website.

The specific flaw exists during the parsing of GIF image components.
When the image width in an image block of a valid GIF file is set to 0,
the Java runtime will allocate the specified size but subsequently copy
all data to the under allocated memory chunk. The overflow results in
the corruption of multiple pointers, at least one of which is later
dereferenced and can therefore result in execution of arbitrary code.

-- Vendor Response:
Sun has issued an update to correct this vulnerability. More details can
be found at:
http://www.sunsolve.sun.com/search/document.do?assetkey=1-26-102760-1

-- Disclosure Timeline:
2006.06.16 - Vulnerability reported to vendor
2006.12.18 - Digital Vaccine released to TippingPoint customers
2007.01.16 - Coordinated public release of advisory

-- Credit:
This vulnerability was discovered by an anonymous researcher.

-- About the Zero Day Initiative (ZDI):
Established by TippingPoint, a division of 3Com, The Zero Day Initiative
(ZDI) represents a best-of-breed model for rewarding security
researchers for responsibly disclosing discovered vulnerabilities.

Researchers interested in getting paid for their security research
through the ZDI can find more information and sign-up at:

    http://www.zerodayinitiative.com

The ZDI is unique in how the acquired vulnerability information is used.
3Com does not re-sell the vulnerability details or any exploit code.
Instead, upon notifying the affected product vendor, 3Com provides its
customers with zero day protection through its intrusion prevention
technology. Explicit details regarding the specifics of the
vulnerability are not exposed to any parties until an official vendor
patch is publicly available. Furthermore, with the altruistic aim of
helping to secure a broader user base, 3Com provides this vulnerability
information confidentially to security vendors (including competitors)
who have a vulnerability protection or mitigation product.