CVE-2012-4143 in Web Browser
Summary
by MITRE
Opera before 12.01 on Windows and UNIX, and before 11.66 and 12.x before 12.01 on Mac OS X, allows user-assisted remote attackers to trick users into downloading and executing arbitrary files via a small window for the download dialog, a different vulnerability than CVE-2012-1924.
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Analysis
by VulDB Data Team • 03/27/2021
This vulnerability affects Opera web browsers across multiple operating systems and represents a sophisticated social engineering attack vector that exploits user trust in the browser's download interface. The flaw exists in Opera versions prior to 12.01 for Windows and UNIX platforms, and versions before 11.66 and 12.x before 12.01 for Mac OS X systems. The vulnerability stems from the browser's download dialog window design that creates an opportunity for attackers to manipulate user interactions through carefully crafted web content. The small window size of the download dialog provides attackers with a strategic advantage to obscure malicious file download prompts while making them appear legitimate to unsuspecting users.
The technical implementation of this vulnerability relies on the browser's user interface design rather than core security mechanisms, making it particularly insidious as it exploits human factors alongside technical weaknesses. Attackers can create web pages that display download dialogs with minimal window sizes, effectively hiding malicious file operations from users who might otherwise notice suspicious downloads. This approach differs significantly from CVE-2012-1924, which addresses different aspects of Opera's download handling, indicating that this vulnerability specifically targets the visual presentation and user interface elements of the download process rather than the underlying file handling or security checks.
The operational impact of this vulnerability extends beyond simple file execution, as it represents a complete breakdown in user interface security that could enable attackers to deliver malware through seemingly legitimate download scenarios. Users may be tricked into executing malicious software when the download dialog appears to be a normal browser operation, potentially leading to complete system compromise. The vulnerability affects multiple operating systems, making it particularly dangerous as attackers can target users across different platforms with a single attack vector. This cross-platform nature aligns with the broader ATT&CK framework's concept of targeting user interface elements that are consistent across operating systems, as described in techniques related to social engineering and user interaction manipulation.
Security professionals should consider this vulnerability as part of the broader category of client-side attack vectors that leverage user interface deception rather than traditional exploit chains. The vulnerability demonstrates how seemingly minor UI design decisions can create significant security risks, particularly when they involve user interaction prompts that are critical to the browser's security model. Organizations should implement comprehensive browser security policies that include regular updates, user education about suspicious download prompts, and monitoring for unusual download patterns. The mitigation strategy should focus on immediate browser updates to patched versions, along with awareness training that emphasizes the importance of verifying download sources and understanding the browser's security interface elements. This vulnerability also highlights the importance of considering human factors in security design, as outlined in CWE categories related to user interface security and social engineering attacks that manipulate user behavior through interface manipulation rather than technical exploits.