CVE-2013-0800 in pixman
Summary
by MITRE
Integer signedness error in the pixman_fill_sse2 function in pixman-sse2.c in Pixman, as distributed with Cairo and used in Mozilla Firefox before 20.0, Firefox ESR 17.x before 17.0.5, Thunderbird before 17.0.5, Thunderbird ESR 17.x before 17.0.5, SeaMonkey before 2.17, and other products, allows remote attackers to execute arbitrary code via crafted values that trigger attempted use of a (1) negative box boundary or (2) negative box size, leading to an out-of-bounds write operation.
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Analysis
by VulDB Data Team • 01/01/2022
The vulnerability identified as CVE-2013-0800 represents a critical integer signedness error within the pixman library's SSE2 implementation, specifically in the pixman_fill_sse2 function located in pixman-sse2.c. This flaw exists within the graphics rendering subsystem that is widely utilized across numerous software applications, including the Mozilla Firefox web browser, Thunderbird email client, and SeaMonkey suite. The issue stems from improper handling of signed integer values during graphics processing operations, creating a scenario where malicious input can cause the application to perform unauthorized memory operations. The vulnerability affects versions of these products prior to Firefox 20.0, Firefox ESR 17.x before 17.0.5, Thunderbird before 17.0.5, Thunderbird ESR 17.x before 17.0.5, and SeaMonkey before 2.17, indicating the widespread nature of this security flaw across the Mozilla ecosystem and related software products.
The technical exploitation of this vulnerability occurs when crafted input values are processed by the graphics rendering engine, specifically triggering either a negative box boundary or negative box size condition. When these invalid values are passed to the pixman_fill_sse2 function, the signed integer handling fails to properly validate the input parameters, resulting in an out-of-bounds write operation. This type of memory corruption vulnerability falls under the CWE-190 category of "Integer Overflow or Wraparound" and specifically manifests as a CWE-787 "Out-of-bounds Write" condition. The flaw allows attackers to manipulate memory layout by writing data beyond the allocated buffer boundaries, which can lead to arbitrary code execution when carefully crafted malicious input is processed by the vulnerable graphics rendering pipeline.
The operational impact of this vulnerability is severe and potentially exploitable in remote attack scenarios. Attackers can leverage this flaw by delivering malicious content through web pages or email attachments that trigger the graphics rendering code path. When the vulnerable application processes such content, the out-of-bounds write operation can overwrite critical memory locations, potentially allowing for code execution with the privileges of the affected application. This vulnerability directly maps to ATT&CK technique T1059.007 "Command and Scripting Interpreter: JavaScript' and T1203 "Exploitation for Client Execution" within the MITRE ATT&CK framework, as it enables remote code execution through browser-based exploitation. The affected applications typically run with user privileges, making successful exploitation potentially dangerous for end users who may inadvertently visit malicious websites or open compromised email attachments.
Mitigation strategies for CVE-2013-0800 involve immediate patching of affected software versions, with vendors releasing updates that correct the integer signedness handling in the pixman library. Users should upgrade to Firefox 20.0 or later, Thunderbird 17.0.5 or later, and SeaMonkey 2.17 or later versions. Additionally, system administrators should implement network-level protections such as web application firewalls and content filtering solutions that can detect and block malicious content targeting these specific vulnerabilities. The fix typically involves proper validation of input parameters to ensure that box boundary and size values remain within valid positive ranges before processing, preventing the conditions that lead to out-of-bounds memory operations. Security monitoring should focus on detecting unusual graphics processing patterns and memory access violations that might indicate exploitation attempts. Organizations should also consider implementing sandboxing mechanisms and privilege separation techniques to limit the potential impact of successful exploitation, as this vulnerability could potentially allow attackers to execute arbitrary code with the privileges of the affected application.