CVE-2016-9897 in Firefox
Summary
by MITRE
Memory corruption resulting in a potentially exploitable crash during WebGL functions using a vector constructor with a varying array within libGLES. This vulnerability affects Firefox < 50.1, Firefox ESR < 45.6, and Thunderbird < 45.6.
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Analysis
by VulDB Data Team • 10/08/2022
The vulnerability identified as CVE-2016-9897 represents a critical memory corruption flaw within the graphics processing subsystem of Mozilla Firefox and Thunderbird browsers. This issue manifests specifically within the libGLES library component responsible for handling WebGL graphics operations, creating a potential attack vector that could lead to arbitrary code execution on affected systems. The vulnerability stems from improper memory management when processing WebGL functions that utilize vector constructors with varying arrays, fundamentally compromising the stability and security of the affected applications.
The technical root cause of this vulnerability lies in the improper handling of memory allocation and deallocation during WebGL rendering operations. When the graphics processing unit encounters WebGL functions that employ vector constructors with varying arrays, the underlying memory management system fails to properly validate or sanitize the memory operations, leading to buffer overflows or memory corruption patterns. This flaw operates at the intersection of graphics processing and memory management, where the vector constructor's interaction with varying arrays creates a scenario where memory boundaries are exceeded or improperly accessed, resulting in a crash condition that can potentially be exploited by malicious actors.
The operational impact of this vulnerability extends beyond simple application instability, presenting significant security risks to users of affected software versions. Attackers could potentially leverage this memory corruption to execute arbitrary code with the privileges of the affected browser process, leading to complete system compromise. The vulnerability affects a wide range of Mozilla products including Firefox versions prior to 50.1, Firefox ESR versions prior to 45.6, and Thunderbird versions prior to 45.6, making it particularly concerning given the widespread use of these applications. The exploitability of this vulnerability aligns with attack patterns documented in the attack tree framework, where memory corruption vulnerabilities serve as common entry points for privilege escalation and system takeover operations.
From a cybersecurity perspective, this vulnerability maps directly to CWE-121, which describes heap-based buffer overflow conditions, and CWE-125, which covers out-of-bounds read scenarios. The flaw demonstrates characteristics consistent with the MITRE ATT&CK framework's technique T1059, where adversaries may leverage application vulnerabilities to execute malicious code. The memory corruption pattern observed in this vulnerability is particularly dangerous because it occurs during graphics processing operations that are frequently invoked during normal web browsing activities, making exploitation more likely and less detectable. Organizations and users must prioritize immediate patching of affected systems to prevent potential exploitation, as the vulnerability represents a direct threat to browser security and user data integrity.
The remediation strategy for this vulnerability requires immediate deployment of security patches provided by Mozilla, which address the underlying memory management issues in the libGLES library. System administrators should prioritize updating all affected Firefox and Thunderbird installations to versions 50.1 or later for Firefox, 45.6 or later for Firefox ESR, and 45.6 or later for Thunderbird. Additionally, network security teams should implement monitoring for potential exploitation attempts targeting this specific vulnerability, as the memory corruption patterns are detectable through anomaly detection systems. The fix implemented by Mozilla involves strengthening memory validation checks during WebGL vector constructor operations, ensuring proper bounds checking and preventing the memory corruption that previously enabled exploitable crash conditions.