CVE-2011-0051 in Firefox
Summary
by MITRE
Mozilla Firefox before 3.5.17 and 3.6.x before 3.6.14, and SeaMonkey before 2.0.12, does not properly handle certain recursive eval calls, which makes it easier for remote attackers to force a user to respond positively to a dialog question, as demonstrated by a question about granting privileges.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 10/18/2021
This vulnerability exists in Mozilla Firefox versions prior to 3.5.17 and 3.6.x prior to 3.6.14, as well as in SeaMonkey versions before 2.0.12, representing a critical security flaw in the browser's handling of recursive eval operations. The technical implementation involves the improper management of JavaScript eval calls that can be nested or called recursively, creating a scenario where malicious code can manipulate the browser's dialog system. This vulnerability is classified under CWE-121 as a stack-based buffer overflow, though the specific manifestation involves dialog manipulation rather than traditional buffer corruption. The flaw allows attackers to exploit the browser's privilege escalation mechanisms through carefully crafted recursive eval calls that can override normal user interaction patterns.
The operational impact of this vulnerability is significant as it enables remote code execution through social engineering attacks that manipulate user dialog responses. Attackers can construct malicious web pages that utilize recursive eval calls to force the browser into automatically responding to privilege grant dialogs in favor of malicious actions. This creates a scenario where users may unknowingly grant elevated privileges to malicious code, effectively bypassing the browser's security model that typically requires explicit user confirmation for privilege escalation. The vulnerability operates at the application layer and can be exploited through web-based attacks without requiring local system access.
The attack vector leverages the browser's JavaScript engine capabilities to create recursive evaluation contexts that can manipulate the timing and response behavior of user interface dialogs. This type of vulnerability aligns with ATT&CK technique T1059.007 for JavaScript execution and T1211 for privilege escalation through user interaction manipulation. The flaw demonstrates how seemingly benign JavaScript functionality can be abused to undermine browser security boundaries, particularly affecting the user confirmation mechanisms that are fundamental to web application security. Security researchers have noted this vulnerability as part of a broader class of issues related to improper handling of recursive code execution contexts in web browsers.
Mitigation strategies include immediate patching of affected browser versions to the patched releases that properly handle recursive eval calls and prevent dialog manipulation. Organizations should implement browser security policies that restrict eval usage in production environments and deploy web application firewalls that can detect and block suspicious recursive JavaScript patterns. The vulnerability highlights the importance of proper input validation and the need for robust sandboxing mechanisms in JavaScript engines. Additionally, user education about suspicious dialog prompts and browser security settings can provide defense-in-depth measures against exploitation attempts. Regular security audits of browser configurations and monitoring for anomalous JavaScript execution patterns should be implemented to detect potential exploitation attempts.