CVE-2009-0323 in Amaya Web Browser
Summary
by MITRE
Multiple stack-based buffer overflows in W3C Amaya Web Browser 10.0 and 11.0 allow remote attackers to execute arbitrary code via (1) a long type parameter in an input tag, which is not properly handled by the EndOfXmlAttributeValue function; (2) an "HTML GI" in a start tag, which is not properly handled by the ProcessStartGI function; and unspecified vectors in (3) html2thot.c and (4) xml2thot.c, related to the msgBuffer variable. NOTE: these are different vectors than CVE-2008-6005.
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Analysis
by VulDB Data Team • 05/16/2025
The vulnerability described in CVE-2009-0323 represents a critical security flaw affecting W3C Amaya Web Browser versions 10.0 and 11.0, specifically targeting stack-based buffer overflow conditions that enable remote code execution. This vulnerability stems from inadequate input validation within the browser's HTML parsing mechanisms, creating exploitable conditions that can be triggered through carefully crafted web content. The flaw manifests in multiple distinct code paths, demonstrating the complexity of the underlying security issues and the broad attack surface within the browser's rendering engine.
The technical implementation of this vulnerability involves three primary attack vectors that exploit different functions within the browser's processing pipeline. The first vector occurs when a maliciously crafted HTML input tag contains an excessively long type parameter, which the EndOfXmlAttributeValue function fails to properly handle, leading to stack corruption. The second vector targets the ProcessStartGI function with malformed "HTML GI" data in start tags, while the remaining vectors involve unspecified issues in html2thot.c and xml2thot.c files that specifically relate to improper handling of the msgBuffer variable. These multiple attack surfaces indicate a systemic weakness in the browser's input sanitization and memory management practices.
From an operational perspective, this vulnerability presents a severe threat to users of the affected browser versions, as remote attackers can leverage these buffer overflows to execute arbitrary code with the privileges of the affected user. The stack-based nature of these overflows means that attackers can potentially overwrite return addresses and function pointers, allowing for complete system compromise. The vulnerability's classification under CWE-121 stack-based buffer overflow highlights the fundamental issue of insufficient boundary checking in memory operations, while the attack vectors align with techniques documented in the ATT&CK framework under the T1059.007 execution technique for command and scripting interpreter. The fact that these are distinct vectors from CVE-2008-6005 indicates that the vulnerability represents a separate class of memory corruption issues rather than a simple regression.
The mitigation strategies for this vulnerability primarily focus on immediate remediation through software updates and patches provided by the W3C development team. Organizations should prioritize updating to patched versions of the Amaya browser to eliminate these exploitable conditions. Additionally, network administrators should implement web content filtering solutions that can detect and block malicious HTML content containing overly long parameters or malformed tags that could trigger these buffer overflows. Input validation should be strengthened at multiple levels including client-side and server-side processing, with particular attention to ensuring proper bounds checking in HTML parsing functions. The vulnerability serves as a reminder of the importance of robust memory management practices and comprehensive input validation in web browser implementations, with recommendations aligning with industry best practices for preventing buffer overflow exploits.