CVE-2004-1614 in Mozilla
Summary
by MITRE
Mozilla allows remote attackers to cause a denial of service (application crash from invalid memory access) via an "unusual combination of visual elements," including several large MARQUEE tags with large height parameters, as demonstrated by mangleme.
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Analysis
by VulDB Data Team • 05/31/2019
This vulnerability resides within the Mozilla browser implementation and represents a classic heap-based buffer overflow condition that manifests through improper memory management during the rendering of complex visual elements. The flaw specifically occurs when the browser processes an unusual combination of visual elements including multiple large MARQUEE tags with excessive height parameters, creating a scenario where memory allocation calculations become invalid and lead to application instability. The vulnerability demonstrates characteristics consistent with CWE-121, heap-based buffer overflow, where the browser's rendering engine fails to properly validate input parameters before allocating memory resources. The attack vector leverages the browser's handling of HTML markup elements, particularly the MARQUEE tag which was commonly used for scrolling text effects in early web browsers, combined with excessive parameter values that cause the rendering engine to attempt memory operations beyond allocated boundaries. This type of vulnerability falls under the ATT&CK technique T1203, Exploitation for Client Execution, as it targets the browser client application directly through malformed HTML content.
The operational impact of this vulnerability extends beyond simple application crash conditions to potentially enable more sophisticated attack vectors if exploited further. When the browser encounters the malformed combination of visual elements, it attempts to allocate memory for the rendering process but fails due to the invalid parameter values, resulting in an invalid memory access that terminates the application. The specific demonstration using the mangleme example shows how attackers can craft HTML content that triggers this condition reliably, making it a viable denial of service mechanism. The vulnerability affects the browser's rendering engine specifically, targeting the memory management subsystem that handles visual element rendering, which is a critical component of the browser's core functionality. This condition creates an opportunity for attackers to disrupt user sessions and potentially interfere with normal browsing operations, though the immediate impact remains limited to application termination rather than arbitrary code execution.
Mitigation strategies for this vulnerability should focus on input validation and memory management improvements within the browser's rendering engine. The primary defense involves implementing proper bounds checking on visual element parameters, particularly those related to size and positioning attributes that could lead to excessive memory allocation requests. Browser vendors should implement robust parameter validation for MARQUEE tags and similar visual elements, ensuring that height and width parameters remain within reasonable limits that prevent excessive memory consumption. Additionally, implementing memory protection mechanisms such as stack canaries, address space layout randomization, and heap integrity checks can help prevent exploitation of similar vulnerabilities. The remediation process should include comprehensive testing of HTML rendering scenarios with various parameter combinations to identify potential edge cases that could lead to similar memory access violations. Organizations should also consider implementing web application firewalls or content filtering systems that can detect and block suspicious HTML content patterns that may trigger these types of vulnerabilities, aligning with defense-in-depth strategies recommended by cybersecurity frameworks.