CVE-2011-0686 in Web Browser
Summary
by MITRE
Unspecified vulnerability in Opera before 11.01 allows remote attackers to cause a denial of service (application crash) via unknown content on a web page, as demonstrated by vkontakte.ru.
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Analysis
by VulDB Data Team • 10/13/2021
The vulnerability identified as CVE-2011-0686 represents a critical security flaw in Opera web browsers prior to version 11.01, where remote attackers could exploit unspecified content on web pages to trigger application crashes and subsequent denial of service conditions. This vulnerability specifically targeted the browser's rendering engine and content processing mechanisms, allowing malicious actors to craft web content that would cause the Opera browser to terminate unexpectedly. The exploit was demonstrated against vkontakte.ru, a major social networking platform, highlighting the real-world impact and potential for widespread disruption through this vulnerability. The unspecified nature of the flaw suggests it may have involved multiple attack vectors or underlying technical issues within Opera's browser architecture that were not fully documented at the time of disclosure.
The technical implementation of this vulnerability likely involved manipulating HTML, CSS, or JavaScript elements in ways that would cause memory corruption, buffer overflows, or improper handling of malformed content within Opera's rendering pipeline. Such flaws typically occur when browsers fail to properly validate or sanitize content before processing it, creating opportunities for attackers to craft malicious payloads that exploit memory management issues or parsing inconsistencies. The vulnerability's classification as a denial of service issue indicates that while it may not have enabled direct code execution or data theft, it could effectively render the browser unusable for legitimate users, creating significant operational disruption. This type of vulnerability falls under CWE-122, which encompasses buffer overflow conditions, and aligns with ATT&CK techniques for privilege escalation and denial of service through application-level exploits.
The operational impact of CVE-2011-0686 extended beyond simple browser crashes, as it could be leveraged to disrupt user productivity and create security concerns for organizations relying on Opera browsers. When exploited at scale, such vulnerabilities could cause cascading effects across corporate networks where Opera was the primary browser, potentially leading to widespread service disruption and requiring immediate patch deployment across affected systems. The vulnerability's demonstration against a high-traffic website like vkontakte.ru underscored the potential for mass impact, as users visiting compromised pages would experience unexpected browser termination. Organizations needed to implement immediate mitigation strategies including browser updates, network-based content filtering, and user education to prevent exploitation. The vulnerability highlighted the importance of regular security updates and the risks associated with using outdated browser versions, as Opera 11.01 addressed these specific issues through enhanced input validation and memory management improvements. This incident reinforced industry best practices for vulnerability management and demonstrated how seemingly minor flaws in browser implementations could have significant operational consequences for both individual users and enterprise environments.