CVE-2017-14829 in Foxit
Summary
by MITRE
This vulnerability allows remote attackers to execute arbitrary code on vulnerable installations of Foxit Reader 8.3.1.21155. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file. The specific flaw exists within the openList method of XFAScriptObject objects. The issue results from the lack of proper validation of user-supplied data, which can result in a type confusion condition. An attacker can leverage this to execute code in the context of the current process. Was ZDI-CAN-5021.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 12/16/2019
CVE-2017-14829 represents a critical type confusion vulnerability affecting Foxit Reader version 8.3.1.21155 that enables remote code execution through carefully crafted malicious content. This vulnerability resides within the XFAScriptObject's openList method, where insufficient input validation allows attackers to manipulate object types during runtime execution. The flaw stems from a fundamental lack of proper data validation mechanisms that should have prevented the exploitation of type confusion conditions. According to CWE-476, this vulnerability directly maps to a null pointer dereference scenario where the application fails to properly validate object types, creating an opportunity for attackers to manipulate memory structures. The attack requires user interaction through visiting a malicious webpage or opening a specially crafted file, making it a client-side exploitation vector that aligns with ATT&CK technique T1203 for exploitation for execution. The vulnerability's impact extends beyond simple privilege escalation as it allows attackers to execute arbitrary code within the context of the current process, effectively bypassing standard security boundaries. This type confusion condition occurs when the application improperly handles object references, leading to memory corruption that can be leveraged for privilege escalation. The vulnerability's classification as a remote code execution flaw means that attackers can compromise systems without requiring physical access or local network presence, making it particularly dangerous in enterprise environments. The attack vector demonstrates the classic pattern of exploiting scripting engine vulnerabilities where user-supplied data flows through application layers without adequate sanitization. Security researchers have documented similar patterns in Adobe Reader and other PDF processing applications where type confusion vulnerabilities have been successfully exploited in the wild. The lack of proper input validation in the XFAScriptObject implementation creates a dangerous condition where attacker-controlled data can influence object behavior and memory layout. This vulnerability aligns with industry standards that emphasize the importance of input validation and proper object lifecycle management in preventing memory corruption exploits. The exploitation of this vulnerability can result in complete system compromise, as attackers can leverage the elevated privileges of the running process to install malware, steal sensitive data, or establish persistent backdoors. Organizations should prioritize immediate patching of affected systems, as the vulnerability's remote nature and requirement for minimal user interaction make it particularly attractive to threat actors. The incident highlights the critical importance of secure coding practices and proper memory management in applications that process untrusted content, especially in document readers and similar software that must handle complex data structures.