CVE-2011-2629 in Web Browser
Summary
by MITRE
Unspecified vulnerability in Opera before 11.11 allows remote attackers to cause a denial of service (application crash) via unknown content on a web page, as demonstrated by www.falk.de.
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Analysis
by VulDB Data Team • 11/14/2021
The vulnerability identified as CVE-2011-2629 represents a critical security flaw in Opera web browsers prior to version 11.11, specifically categorized under the broader class of denial of service vulnerabilities. This issue demonstrates how seemingly innocuous web content can be weaponized to disrupt browser operations and compromise user experience. The vulnerability manifests when Opera encounters specific malformed or malicious content on web pages, leading to unexpected application crashes that can be exploited remotely by attackers. The targeted nature of this flaw highlights the importance of browser security in protecting users from remote exploitation vectors.
Technical analysis reveals that this vulnerability operates at the application layer of the browser's processing pipeline, where content rendering engines encounter malformed data structures that trigger memory corruption or improper handling of web page elements. The unspecified nature of the vulnerable content suggests that multiple attack vectors could potentially trigger the same underlying flaw, making the vulnerability particularly concerning for security professionals. The demonstration of this vulnerability through the www.falk.de website indicates that it was likely triggered by specific HTML or JavaScript elements that caused Opera's rendering engine to fail during normal operation, resulting in complete application termination.
The operational impact of CVE-2011-2629 extends beyond simple inconvenience, as it represents a potential vector for more sophisticated attacks that could be combined with other exploits to achieve broader compromise objectives. When a browser crashes remotely, it can provide attackers with opportunities to disrupt user workflows, potentially leading to more serious security incidents. The vulnerability's remote exploitation capability means that users could be attacked simply by visiting a compromised website, without any interaction required from the user beyond normal browsing behavior. This characteristic aligns with attack patterns commonly associated with the attack technique of web-based exploitation in the MITRE ATT&CK framework.
From a security standards perspective, this vulnerability relates to CWE-119 Improper Access to Memory and CWE-122 Heap-based Buffer Overflow, both of which describe memory handling flaws that can lead to application instability and crashes. The vulnerability also demonstrates characteristics of the broader class of software defects that can be exploited through the use of malformed input, which is a fundamental concern in the OWASP Top Ten security risks. Organizations and users affected by this vulnerability needed to implement immediate mitigation strategies including browser updates, network-based filtering, and user education to prevent exploitation. The incident underscores the critical importance of maintaining current browser versions and implementing robust security practices to protect against remote code execution and denial of service attacks that can compromise user systems and data integrity.
The remediation approach for this vulnerability required users to upgrade to Opera version 11.11 or later, which included patches addressing the memory handling issues that caused the application crashes. Security administrators needed to prioritize this update across their organization's systems, as the vulnerability could be exploited without user interaction, making it particularly dangerous in enterprise environments. The vulnerability serves as a reminder of the importance of regular security updates and the potential consequences of running outdated software versions that may contain known security flaws.