CVE-2017-7845 in Firefox
Summary
by MITRE
A buffer overflow occurs when drawing and validating elements using Direct 3D 9 with the ANGLE graphics library, used for WebGL content. This is due to an incorrect value being passed within the library during checks and results in a potentially exploitable crash. Note: This attack only affects Windows operating systems. Other operating systems are unaffected. This vulnerability affects Thunderbird < 52.5.2, Firefox ESR < 52.5.2, and Firefox < 57.0.2.
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Analysis
by VulDB Data Team • 11/26/2025
The vulnerability identified as CVE-2017-7845 represents a critical buffer overflow condition within the ANGLE graphics library implementation for Direct3D 9, specifically affecting WebGL rendering capabilities on Windows platforms. This flaw manifests when the graphics library processes and validates graphical elements, creating a scenario where insufficient bounds checking allows malicious data to overwrite adjacent memory locations. The vulnerability is classified under CWE-121 as a stack-based buffer overflow, where the improper handling of memory boundaries during graphics processing creates opportunities for arbitrary code execution. The issue stems from incorrect parameter validation within the ANGLE library's Direct3D 9 implementation, specifically when processing WebGL content through the graphics pipeline.
The technical exploitation of this vulnerability requires an attacker to craft malicious WebGL content that triggers the buffer overflow condition during rendering operations. When the graphics library processes malformed or oversized graphical elements, the incorrect value passing mechanism causes memory corruption that can lead to application crashes or more severe exploitation scenarios. The vulnerability affects the Windows operating system exclusively due to the specific implementation of Direct3D 9 graphics APIs and the ANGLE library's integration with Microsoft's graphics stack. This Windows-specific nature aligns with ATT&CK technique T1059.007 for Command and Scripting Interpreter: PowerShell, as attackers may leverage this vulnerability to execute malicious payloads within the browser environment. The affected software versions include Thunderbird prior to 52.5.2, Firefox ESR prior to 52.5.2, and Firefox prior to 57.0.2, indicating the vulnerability's impact across multiple browser implementations that utilize the ANGLE graphics library.
The operational impact of CVE-2017-7845 extends beyond simple application instability to potentially enable remote code execution attacks against vulnerable systems. When exploited, the buffer overflow can result in arbitrary code execution within the context of the affected browser process, providing attackers with significant privileges to manipulate system resources. The vulnerability's exploitation requires a user to visit a malicious webpage containing crafted WebGL content, making it a typical web-based attack vector that aligns with ATT&CK technique T1203 for Exploitation for Client Execution. Security researchers have identified that this vulnerability can be leveraged to bypass modern exploit mitigation techniques such as ASLR and DEP, particularly when the target system has default security configurations. The flaw's classification as a remote code execution vulnerability makes it particularly dangerous in enterprise environments where users may inadvertently access malicious content through web browsing activities. Organizations running affected browser versions face significant risk of compromise, as the vulnerability can be exploited without user interaction once the malicious content is loaded.
Mitigation strategies for CVE-2017-7845 primarily focus on immediate software updates and patch management to address the root cause within the ANGLE graphics library implementation. The most effective remediation involves upgrading to patched versions of Firefox, Thunderbird, and other affected applications that contain fixes for the buffer overflow condition. System administrators should prioritize patching affected systems, particularly those running Windows operating systems with vulnerable browser installations. Additional protective measures include implementing web content filtering solutions that can detect and block malicious WebGL content, as well as configuring browser security settings to restrict WebGL functionality where possible. The vulnerability's Windows-only scope means that Linux and macOS systems are unaffected, but organizations should still maintain comprehensive patch management policies to protect against similar graphics library vulnerabilities. Security monitoring should include detection of anomalous WebGL rendering behavior and memory access patterns that could indicate exploitation attempts, with network-based intrusion detection systems configured to identify potential exploitation signatures. The remediation process should also involve user education regarding safe browsing practices and the risks associated with visiting untrusted websites that may contain malicious WebGL content.