CVE-2015-4521 in Firefox
Summary
by MITRE
The ConvertDialogOptions function in Mozilla Firefox before 41.0 and Firefox ESR 38.x before 38.3 might allow remote attackers to cause a denial of service (memory corruption and application crash) or possibly have unspecified other impact via unknown vectors.
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Analysis
by VulDB Data Team • 10/22/2024
The vulnerability identified as CVE-2015-4521 represents a critical memory corruption issue within Mozilla Firefox's ConvertDialogOptions function, affecting versions prior to 41.0 and Firefox ESR 38.x prior to 38.3. This flaw exists within the browser's handling of dialog options during conversion processes, creating potential attack vectors that could be exploited by remote threat actors. The vulnerability's classification as a memory corruption issue indicates that malicious inputs could manipulate heap memory structures, potentially leading to arbitrary code execution or complete application compromise. The unspecified nature of the potential impacts suggests that attackers might leverage this vulnerability for more sophisticated attacks beyond simple denial of service, including privilege escalation or information disclosure.
The technical implementation of this vulnerability stems from improper memory management within the dialog conversion subsystem of Firefox's rendering engine. When the ConvertDialogOptions function processes user input or web content containing malformed dialog parameters, it fails to properly validate or sanitize the input before performing memory operations. This lack of proper input validation creates opportunities for buffer overflows, use-after-free conditions, or other memory corruption scenarios that can be triggered through crafted web pages or malicious content. The vulnerability's location within the dialog processing pipeline suggests that it could be exploited through various web-based attack vectors including web pages, iframes, or even through compromised websites that load malicious content. The attack surface extends beyond simple web browsing to include any functionality that relies on dialog option conversion, making it particularly dangerous for browser environments where users interact with diverse web content.
The operational impact of CVE-2015-4521 extends beyond simple application crashes to potentially enable more sophisticated attack scenarios that could compromise user systems. Remote attackers could leverage this vulnerability to cause persistent denial of service conditions that would prevent legitimate users from accessing web resources, or they could use the memory corruption to execute malicious code with the privileges of the browser process. The potential for unspecified other impacts indicates that this vulnerability could serve as a stepping stone for more advanced attacks, including privilege escalation to system-level access or data exfiltration from the victim's machine. Organizations relying on affected Firefox versions would face significant security risks as this vulnerability could be exploited in the wild without requiring user interaction beyond visiting compromised websites, making it particularly dangerous for enterprise environments where users might encounter malicious content through various attack vectors.
Mitigation strategies for CVE-2015-4521 should prioritize immediate patch deployment to upgrade to Firefox versions 41.0 or later, or Firefox ESR 38.3 and subsequent releases. Security administrators should implement comprehensive monitoring for exploitation attempts through network traffic analysis and web application firewalls that can detect anomalous dialog option processing patterns. Browser hardening measures including disabling unnecessary dialog functionality, implementing strict content security policies, and employing sandboxing techniques can provide additional defense layers against exploitation attempts. The vulnerability's characteristics align with CWE-121, which describes heap-based buffer overflow conditions, and could potentially map to ATT&CK techniques involving privilege escalation through memory corruption vulnerabilities. Organizations should also consider implementing user education programs to avoid visiting untrusted websites and ensure that automated patch management systems are configured to deploy Firefox updates promptly. Regular security assessments of web applications and browser configurations should include checks for vulnerable Firefox versions to prevent exploitation attempts that could lead to more severe security incidents.