CVE-2007-6522 in Web Browser
Summary
by MITRE
The rich text editing functionality in Opera before 9.25 allows remote attackers to conduct cross-domain scripting attacks by using designMode to modify contents of pages in other domains.
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Analysis
by VulDB Data Team • 08/01/2019
The vulnerability described in CVE-2007-6522 represents a critical security flaw in Opera web browser versions prior to 9.25 that stems from improper implementation of rich text editing features. This issue specifically affects the browser's handling of designMode functionality which is typically used to enable contenteditable regions in web pages. The vulnerability arises when Opera's rich text editor attempts to manipulate content from different domains without proper cross-origin security restrictions, creating an avenue for malicious actors to execute unauthorized code across domain boundaries.
The technical implementation flaw occurs within Opera's browser engine where the designMode API is improperly constrained when dealing with cross-domain content. When a web page attempts to set designMode on an element that contains content from another domain, the browser fails to enforce the same-origin policy that normally prevents such cross-domain modifications. This allows attackers to inject malicious scripts into pages from different domains, effectively bypassing the browser's security model that should prevent such operations. The vulnerability specifically leverages the ability to modify contentEditable regions that span across domain boundaries, creating a pathway for cross-domain scripting attacks.
The operational impact of this vulnerability is significant as it enables remote attackers to perform cross-domain scripting attacks that can compromise user sessions, steal sensitive information, or manipulate content across different websites. Attackers can exploit this flaw by crafting malicious web pages that, when loaded in Opera browsers, can modify content on legitimate sites that users visit. This creates a dangerous scenario where users can be attacked through seemingly benign web content, potentially leading to session hijacking, data theft, or defacement of trusted websites. The vulnerability essentially breaks down the fundamental security boundary that separates different web domains, allowing attackers to perform unauthorized operations across the entire web browsing environment.
This vulnerability maps directly to CWE-94, which describes the weakness of allowing code to be executed in the context of a different domain, and aligns with ATT&CK technique T1059.007 for script-based execution. The security implications extend beyond simple cross-site scripting as this represents a complete breakdown of the browser's cross-origin security model, creating a persistent threat vector that can be exploited across multiple domains. Organizations should consider implementing browser security policies that restrict the use of designMode functionality, and users should be encouraged to keep their browsers updated to versions that have patched this vulnerability. The mitigation strategy requires browser vendors to enforce proper cross-origin restrictions on designMode operations and to implement additional security layers that prevent unauthorized content modification across domain boundaries.