CVE-2007-3550 in Internet Explorer
Summary
by MITRE
** DISPUTED ** Microsoft Internet Explorer 6.0 and 7.0 allows remote attackers to fill Zones with arbitrary domains using certain metacharacters such as wildcards via JavaScript, which results in a denial of service (website suppression and resource consumption), aka "Internet Explorer Zone Domain Specification Dos and Page Suppressing". NOTE: this issue has been disputed by a third party, who states that the zone settings cannot be manipulated.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 06/07/2025
This vulnerability affects Microsoft Internet Explorer versions 6.0 and 7.0, specifically targeting the browser's zone management system that controls security boundaries for different types of web content. The issue stems from how Internet Explorer handles domain specifications within security zones, particularly when certain metacharacters like wildcards are used in JavaScript contexts. The vulnerability is categorized under CWE-129, which deals with insufficient validation of the length or value of input data, and relates to improper handling of special characters in security context definitions. The disputed nature of this CVE reflects ongoing debate within the security community regarding the actual exploitability and impact of the reported flaw.
The technical implementation involves JavaScript code that can manipulate zone domain specifications through the use of wildcard characters and other metacharacters to create invalid domain patterns. When Internet Explorer processes these malformed domain specifications, it fails to properly validate the input, potentially leading to memory corruption or excessive resource consumption during zone evaluation. This behavior manifests as denial of service conditions where legitimate websites may be suppressed or the browser may consume excessive system resources, effectively preventing normal browsing operations. The vulnerability operates at the application layer and requires user interaction through malicious JavaScript code execution.
The operational impact of this vulnerability extends beyond simple denial of service scenarios, as it represents a potential pathway for more sophisticated attacks. Attackers could leverage this flaw to disrupt legitimate web services by causing browsers to misclassify domains or consume excessive computational resources. The suppression of websites could be used to hide malicious content or prevent users from accessing legitimate resources. From an attacker's perspective, this vulnerability aligns with ATT&CK technique T1133 (External Remote Services) and T1059.007 (Command and Scripting Interpreter: JavaScript), as it enables manipulation of browser security policies through script-based attacks. The vulnerability demonstrates the importance of input validation in security-critical applications and highlights the risks associated with improper handling of special characters in security context management.
Mitigation strategies should focus on immediate browser updates and security patches from Microsoft, as well as implementing additional security measures such as browser sandboxing and strict content security policies. Organizations should consider disabling JavaScript in trusted zones or implementing additional input validation mechanisms to prevent exploitation. The vulnerability underscores the importance of proper input sanitization and validation in security-critical applications, particularly those handling user-supplied data that could influence system behavior. Regular security assessments and monitoring for unusual resource consumption patterns can help detect exploitation attempts. This vulnerability also emphasizes the need for comprehensive security testing of application layer components that handle user input in security-sensitive contexts, as highlighted by the CWE-129 category and related security standards.