CVE-2010-4047 in Web Browser
Summary
by MITRE
Opera before 10.63 does not properly select the security context of JavaScript code associated with an error page, which allows user-assisted remote attackers to conduct cross-site scripting (XSS) attacks via a crafted web site.
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Analysis
by VulDB Data Team • 09/28/2021
The vulnerability identified as CVE-2010-4047 represents a critical security flaw in Opera web browsers prior to version 10.63, specifically related to how the browser handles JavaScript execution contexts when displaying error pages. This issue stems from improper security context selection during error page rendering, creating a pathway for malicious actors to exploit cross-site scripting vulnerabilities through carefully crafted web content. The flaw exists in the browser's handling of JavaScript code execution within error page contexts, where the security boundaries between legitimate error page content and potentially malicious script code become blurred. Attackers can leverage this vulnerability by constructing malicious websites that trigger error conditions in the Opera browser, subsequently executing arbitrary JavaScript code within the context of the vulnerable browser. This improper context handling creates an environment where user-supplied content can be interpreted as executable script rather than benign error display information.
The technical root cause of this vulnerability aligns with CWE-79, which describes cross-site scripting flaws where web applications fail to properly validate or escape user input before rendering it in web pages. In this case, the vulnerability manifests during error page processing where the browser's security model fails to maintain proper isolation between different JavaScript execution contexts. When Opera encounters an error condition, it should maintain strict security boundaries between the error page rendering context and any associated JavaScript code. However, the browser's implementation allows for JavaScript code from error pages to execute in contexts where it could interact with the main browsing context, creating an attack surface for XSS exploitation. The vulnerability specifically impacts how the browser selects security contexts for JavaScript execution, particularly when error pages contain embedded scripts that should be isolated from normal browsing operations.
The operational impact of CVE-2010-4047 extends beyond simple XSS attacks, as it enables attackers to potentially access sensitive user data, perform actions on behalf of users, and compromise the overall security of the browser environment. When successfully exploited, this vulnerability allows attackers to inject malicious scripts that can access cookies, session information, and other sensitive data stored within the browser. The user-assisted nature of this attack means that victims must visit a malicious website, but once triggered, the exploitation can occur without additional user interaction. This makes the vulnerability particularly dangerous in environments where users may encounter malicious content through social engineering or compromised websites. The attack vector specifically targets the error page handling mechanism, which is frequently encountered during normal web browsing operations, making the exploitation relatively common and difficult to defend against through traditional user education methods alone.
Mitigation strategies for CVE-2010-4047 focus primarily on updating to Opera version 10.63 or later, which contains the necessary security patches to properly isolate JavaScript execution contexts during error page rendering. System administrators should implement immediate browser updates across all affected systems and consider deploying additional security measures such as content filtering and web application firewalls to provide defense-in-depth. Organizations should also consider implementing browser security policies that restrict JavaScript execution in error contexts and regularly audit their browser configurations to ensure proper security boundaries are maintained. The vulnerability demonstrates the importance of proper context management in web browsers, particularly during error handling operations where security boundaries are most critical. This issue aligns with ATT&CK technique T1059.007 for JavaScript execution and T1211 for exploitation of browser vulnerabilities, emphasizing the need for comprehensive browser security management and regular patching procedures to maintain protection against similar vulnerabilities in the future.