CVE-2014-8092 in X11
Summary
by MITRE
Multiple integer overflows in X.Org X Window System (aka X11 or X) X11R1 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) ProcPutImage, (2) GetHosts, (3) RegionSizeof, or (4) REQUEST_FIXED_SIZE function, which triggers an out-of-bounds read or write.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 08/29/2025
The vulnerability identified as CVE-2014-8092 represents a critical security flaw in the X.Org X Window System, specifically affecting versions prior to 1.16.3. This issue manifests through multiple integer overflow conditions that can be exploited by remote authenticated users to compromise system stability and potentially execute arbitrary code. The affected components include the core X11R1 and X.Org Server implementations, commonly referred to as xserver and xorg-server, which form the foundation of graphical user interfaces in Unix-like operating systems. The vulnerability impacts the fundamental request processing mechanisms within the X Window System, making it particularly dangerous as it affects core functionality that applications depend upon for graphical operations.
The technical flaw stems from improper handling of integer values during request processing, specifically within four critical functions: ProcPutImage, GetHosts, RegionSizeof, and REQUEST_FIXED_SIZE. These functions process various types of requests from clients to the X server, and the integer overflows occur when calculating buffer sizes or array indices based on user-provided input. When an attacker sends a crafted request containing maliciously formatted data, the integer overflow can result in memory corruption that manifests as either out-of-bounds read or write operations. This type of vulnerability is classified under CWE-190 as an integer overflow condition, which is a well-documented weakness in software security that occurs when an integer value exceeds the maximum value that can be represented by its data type. The vulnerability's exploitation requires authentication, meaning that an attacker must already have access to the system to send malicious requests, but this access can be gained through various attack vectors including network-based authentication mechanisms.
The operational impact of CVE-2014-8092 extends beyond simple denial of service, though that remains a significant concern. While the primary effect is a system crash that can be leveraged for denial of service attacks, the integer overflow conditions also present opportunities for arbitrary code execution, making this vulnerability particularly dangerous in multi-user environments. The affected functions are commonly used in graphical applications, making exploitation more likely in environments where users interact with X11-based applications. This vulnerability affects the core X server functionality, meaning that any application relying on X11 graphics operations could potentially be compromised. The attack surface is broad given that X11 is used across numerous Unix-like systems including Linux distributions, BSD variants, and other operating systems that implement the X Window System. Organizations running affected versions of X.Org Server are particularly vulnerable as the flaw exists at the protocol level, affecting all applications that communicate with the X server through standard X11 protocols.
The mitigation strategy for CVE-2014-8092 centers on upgrading to X.Org Server version 1.16.3 or later, which contains patches addressing the integer overflow conditions in the affected functions. System administrators should prioritize updating their X server implementations as part of routine security maintenance, particularly in environments where remote access is possible. Additional mitigations include implementing network segmentation to limit access to X server functionality, using X11 forwarding with SSH to reduce exposure, and monitoring for suspicious X11 traffic patterns. From an ATT&CK framework perspective, this vulnerability maps to techniques involving privilege escalation and remote code execution through protocol manipulation, with the integer overflow representing a foundational weakness that attackers can leverage to gain unauthorized access to systems. Organizations should also consider implementing intrusion detection systems that can identify malicious X11 requests and monitoring for unusual patterns in X server memory usage that might indicate exploitation attempts. The vulnerability demonstrates the importance of proper input validation and integer handling in server applications, emphasizing that even authenticated access can be exploited to cause significant system compromise when underlying security flaws exist in core system components.