CVE-2008-5712 in Konqueror
Summary
by MITRE
The HTML parser in KDE Konqueror 3.5.9 allows remote attackers to cause a denial of service (application crash) via (1) a long COLOR attribute in an HR element; or a long (a) BGCOLOR or (b) BORDERCOLOR attribute in a (2) TABLE, (3) TD, or (4) TR element. NOTE: the FONT vector is already covered by CVE-2008-4514.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 11/07/2024
The vulnerability identified as CVE-2008-5712 represents a classic buffer overflow condition within the HTML parsing component of KDE Konqueror version 3.5.9. This flaw exists in the application's handling of HTML attributes within specific table-related elements, creating a potential denial of service scenario that could be exploited by remote attackers. The vulnerability specifically targets the parser's inability to properly validate or limit the length of certain color attributes, leading to memory corruption that ultimately results in application instability and crash. The issue demonstrates a fundamental weakness in input validation and memory management within the browser's rendering engine, highlighting the importance of robust boundary checking in web content processing.
The technical implementation of this vulnerability occurs when Konqueror encounters HTML elements containing excessively long COLOR attributes within HR elements or BGCOLOR and BORDERCOLOR attributes within TABLE, TD, and TR elements. The parser fails to impose reasonable limits on attribute value lengths, allowing maliciously crafted HTML content to trigger buffer overflow conditions. When the parser attempts to process these oversized attribute values, it overflows the allocated memory buffers, causing the application to terminate unexpectedly. This type of vulnerability falls under CWE-121, which describes stack-based buffer overflow conditions, and specifically aligns with CWE-122, heap-based buffer overflow scenarios that can occur during dynamic memory allocation. The exploitation requires no special privileges and can be executed through standard web browser navigation, making it particularly dangerous in web environments.
The operational impact of CVE-2008-5712 extends beyond simple application instability to potentially enable more sophisticated attack vectors within the broader context of web-based threats. While the immediate effect is a denial of service condition that prevents users from accessing web content through Konqueror, the underlying memory corruption vulnerability could theoretically be leveraged to execute arbitrary code under certain conditions. This vulnerability directly maps to ATT&CK technique T1203, which covers the exploitation of software vulnerabilities to gain unauthorized access or execute malicious code. The attack surface is particularly concerning given that Konqueror was widely used as a web browser in Linux environments, meaning that successful exploitation could compromise numerous systems running affected versions. The vulnerability's persistence across multiple HTML table elements (TABLE, TD, TR) increases its exploitability potential and reduces the effectiveness of simple patching approaches.
Mitigation strategies for CVE-2008-5712 should focus on both immediate defensive measures and long-term architectural improvements. Users should immediately upgrade to Konqueror versions that contain patches addressing this vulnerability, as the original version 3.5.9 was vulnerable to multiple related issues including CVE-2008-4514. System administrators should implement network-level controls to filter potentially malicious HTML content and consider deploying web application firewalls that can detect and block oversized attribute values. The fix should include implementing strict input validation and length limitations for all HTML attribute values, particularly color-related attributes, ensuring that parsers enforce reasonable boundaries for memory allocation. Organizations should also consider implementing security awareness training to help users recognize potentially malicious web content and avoid visiting untrusted websites that might exploit such vulnerabilities. Additionally, regular security assessments and vulnerability scanning should be conducted to identify similar issues in other browser components or web applications that might exhibit similar buffer overflow characteristics.