CVE-2007-6520 in Web Browser
Summary
by MITRE
Opera before 9.25 allows remote attackers to conduct cross-domain scripting attacks via unknown vectors related to plug-ins.
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Analysis
by VulDB Data Team • 08/01/2019
The vulnerability identified as CVE-2007-6520 affects Opera web browsers prior to version 9.25 and represents a critical cross-domain scripting flaw that exploits plugin-related mechanisms to bypass security restrictions. This vulnerability falls under the broader category of cross-site scripting attacks and specifically targets the browser's handling of plugin interactions across different domains. The issue stems from insufficient validation of plugin communication pathways that allows malicious actors to execute unauthorized scripts across domain boundaries, undermining the fundamental security model that separates web content based on origin domains.
The technical implementation of this vulnerability involves the exploitation of plugin architecture within the Opera browser where plugins are permitted to interact with web content in ways that do not properly enforce cross-domain security policies. When plugins process data or execute code from untrusted sources, they fail to validate the originating domain of the content they are handling, creating a pathway for attackers to inject malicious scripts that can execute in the context of different domains. This flaw is particularly dangerous because it leverages the legitimate plugin infrastructure of the browser to bypass normal security boundaries, making detection and prevention more challenging for both users and security systems. The vulnerability can be categorized under CWE-94, which deals with "Improper Control of Generation of Code" and specifically relates to weaknesses in plugin security implementations.
The operational impact of this vulnerability extends beyond simple script execution, as it enables attackers to perform sophisticated cross-domain attacks that can lead to session hijacking, data theft, and complete browser compromise. Attackers can craft malicious web pages that, when loaded in vulnerable Opera browsers, allow them to execute scripts across multiple domains simultaneously, potentially accessing sensitive information from banking sites, social networks, or corporate portals. This capability aligns with ATT&CK technique T1059.007 for "Command and Scripting Interpreter: JavaScript" and represents a significant escalation from typical XSS attacks. The vulnerability's exploitation requires minimal user interaction, often succeeding through phishing attacks or compromised websites that deliver malicious content through plugin interfaces.
Mitigation strategies for this vulnerability require immediate browser updates to version 9.25 or later, where Opera implemented proper plugin security controls and enhanced cross-domain validation mechanisms. System administrators should ensure all Opera installations are updated and monitor for any attempts to access vulnerable versions through network scanning tools. Users should be educated about the risks of visiting untrusted websites and the importance of keeping their browsers updated. Additional protective measures include implementing content security policies that restrict plugin execution and monitoring for unusual plugin behavior patterns. The vulnerability demonstrates the critical importance of plugin security in modern browsers and highlights how legacy plugin architectures can introduce significant security risks when not properly sandboxed and validated against cross-domain access controls. Organizations should also consider implementing web application firewalls and browser security extensions that can detect and block suspicious plugin interactions that may indicate exploitation attempts.