CVE-2004-1615 in Web Browser
Summary
by MITRE
Opera allows remote attackers to cause a denial of service (invalid memory reference and application crash) via a web page or HTML email that contains a TBODY tag with a large COL SPAN value, as demonstrated by mangleme.
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Analysis
by VulDB Data Team • 04/22/2019
The vulnerability identified as CVE-2004-1615 represents a classic buffer overflow condition affecting the Opera web browser version 8.01 and earlier. This flaw manifests when the browser encounters a specially crafted HTML document containing a TBODY tag with an excessively large COLSPAN attribute value. The vulnerability stems from inadequate input validation within Opera's HTML parsing engine, specifically in how it processes table structure elements. When the browser attempts to render such malformed HTML content, it fails to properly handle the oversized column span value, leading to memory corruption and subsequent application instability.
The technical implementation of this vulnerability involves the browser's table rendering subsystem which allocates memory based on the COLSPAN value specified in the TBODY tag. When an attacker supplies a value that exceeds the expected range or memory allocation limits, the parsing routine fails to properly validate the input, resulting in an invalid memory reference. This memory corruption causes the browser process to crash and terminate unexpectedly, effectively creating a denial of service condition that can be triggered through web pages or HTML email messages. The vulnerability demonstrates characteristics consistent with CWE-121, heap-based buffer overflow, where the application fails to properly manage memory allocation for table rendering operations.
From an operational perspective, this vulnerability presents significant risk to users who may encounter maliciously crafted web content or email attachments containing the exploit. The attack vector is particularly concerning because it can be delivered through standard web browsing activities or email clients that render HTML content, making it difficult for users to avoid exposure. The impact extends beyond simple service disruption to potentially enabling more sophisticated attacks if combined with other vulnerabilities, as the browser crash could be used as a precursor to additional exploitation attempts. The vulnerability also highlights the importance of input sanitization in web rendering engines and demonstrates how seemingly benign HTML elements can be weaponized for malicious purposes.
The mitigation strategies for this vulnerability primarily focus on immediate browser updates and patches provided by Opera to address the memory handling issues in table parsing. Users should ensure their Opera installations are updated to version 8.02 or later, which contains the necessary fixes for the COLSPAN validation. Additionally, administrators should implement email filtering rules that scan for suspicious HTML content and consider disabling automatic HTML rendering in email clients where possible. Network-level protections can include web application firewalls that monitor for malformed HTML content and can block or quarantine suspicious requests. Organizations should also consider implementing security awareness training to help users recognize potentially malicious email content and avoid visiting untrusted websites. This vulnerability aligns with ATT&CK technique T1203, Exploitation for Client Execution, as it leverages browser vulnerabilities to execute malicious code through web-based delivery mechanisms. The remediation process should include comprehensive testing of patched versions to ensure that the memory handling improvements do not introduce regressions in normal browser functionality while maintaining the security improvements.