CVE-2014-8093 in XFree86
Summary
by MITRE
Multiple integer overflows in the GLX extension in XFree86 4.0, X.Org X Window System (aka X11 or X) X11R6.7, and X.Org Server (aka xserver and xorg-server) before 1.16.3 allow remote authenticated users to cause a denial of service (crash) or possibly execute arbitrary code via a crafted request to the (1) __glXDisp_ReadPixels, (2) __glXDispSwap_ReadPixels, (3) __glXDisp_GetTexImage, (4) __glXDispSwap_GetTexImage, (5) GetSeparableFilter, (6) GetConvolutionFilter, (7) GetHistogram, (8) GetMinmax, (9) GetColorTable, (10) __glXGetAnswerBuffer, (11) __GLX_GET_ANSWER_BUFFER, (12) __glXMap1dReqSize, (13) __glXMap1fReqSize, (14) Map2Size, (15) __glXMap2dReqSize, (16) __glXMap2fReqSize, (17) __glXImageSize, or (18) __glXSeparableFilter2DReqSize function, which triggers an out-of-bounds read or write.
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Analysis
by VulDB Data Team • 08/29/2025
The vulnerability described in CVE-2014-8093 represents a critical security flaw affecting the X Window System implementation across multiple versions of XFree86 and X.Org Server. This issue stems from integer overflows occurring within the GLX extension, which is responsible for OpenGL graphics rendering capabilities within the X11 windowing system. The affected functions span a wide range of OpenGL texture and image manipulation operations, creating a broad attack surface that could be exploited by authenticated remote attackers. The vulnerability specifically impacts the X11R6.7 release and earlier versions of X.Org Server before 1.16.3, making it a long-standing issue that affected numerous systems running legacy graphics configurations.
The technical root cause of this vulnerability lies in improper input validation and arithmetic overflow handling within the GLX extension's request processing functions. When processing certain OpenGL requests, the system fails to properly validate integer parameters that determine buffer sizes or memory allocation requirements. This leads to situations where crafted malicious requests can cause integer overflows, resulting in out-of-bounds memory access patterns. The vulnerability manifests through multiple specific functions including __glXDisp_ReadPixels, __glXDisp_GetTexImage, and various mapping and filter functions that calculate memory requirements based on user-supplied parameters. These integer overflows can potentially result in memory corruption that may be exploited to execute arbitrary code or cause system crashes.
The operational impact of CVE-2014-8093 extends beyond simple denial of service conditions to potentially enable remote code execution, making it particularly dangerous for systems that support networked OpenGL applications. The vulnerability affects systems where X11 is used for graphics rendering, including servers running X.Org Server, desktop environments, and any application that relies on OpenGL graphics through the X Window System. Attackers can exploit this vulnerability by sending specially crafted GLX requests to a target system, potentially leading to system instability or complete compromise. The integer overflow conditions can cause memory corruption that might be leveraged for privilege escalation or arbitrary code execution, depending on the specific system configuration and memory layout.
Security mitigations for this vulnerability primarily involve updating to patched versions of X.Org Server, specifically versions 1.16.3 and later, which contain proper input validation and integer overflow protections. Organizations should also implement network segmentation to limit access to X11 servers and consider disabling unnecessary GLX extensions where possible. System administrators should conduct thorough vulnerability assessments to identify affected systems and ensure proper patch management protocols are in place. The vulnerability aligns with CWE-190, which describes integer overflow conditions, and relates to ATT&CK techniques involving privilege escalation and remote code execution through system vulnerabilities. Additionally, the issue demonstrates the importance of proper input validation in graphics subsystems and highlights the need for robust memory safety mechanisms in windowing systems that handle external graphics requests.