CVE-2017-14828 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 w method of XFA Layout 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 vulnerability to execute code under the context of the current process. Was ZDI-CAN-5020.
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Analysis
by VulDB Data Team • 12/16/2019
CVE-2017-14828 represents a critical remote code execution vulnerability affecting Foxit Reader version 8.3.1.21155, demonstrating a classic type confusion flaw that enables attackers to gain arbitrary code execution under the privileges of the target process. This vulnerability resides within the w method of XFA Layout objects, which are used for form field layout and formatting in PDF documents. The flaw stems from insufficient validation of user-supplied data during the processing of XFA (XML Forms Architecture) elements, creating a condition where the application incorrectly handles data types during object manipulation. The vulnerability requires user interaction to exploit, meaning an attacker must convince a target to visit a malicious webpage or open a specially crafted malicious file containing the vulnerable XFA content. This attack vector aligns with common social engineering techniques where users are lured into opening seemingly legitimate documents or clicking on malicious links. The type confusion condition occurs when the application's internal type system fails to properly validate the expected data types during processing, allowing an attacker to manipulate memory layout and potentially overwrite critical function pointers or execute arbitrary code. This vulnerability directly maps to CWE-476, which describes NULL pointer dereference conditions, and also relates to CWE-122, which covers heap-based buffer overflow conditions that can occur due to improper type handling. From an operational perspective, this vulnerability presents a significant risk to organizations as it allows remote attackers to execute code on target systems without requiring local access, making it particularly dangerous in enterprise environments where users frequently open PDF documents from untrusted sources. The attack surface extends beyond individual user machines to include any system running vulnerable versions of Foxit Reader, including mobile devices and servers that process PDF documents. The exploitation of this vulnerability can lead to complete system compromise, allowing attackers to install malware, steal sensitive data, or establish persistent backdoors. According to ATT&CK framework, this vulnerability corresponds to T1203, which describes exploitation for execution, and T1059, which covers command and scripting interpreter usage. The security implications extend to potential privilege escalation scenarios where attackers could leverage this vulnerability to gain elevated system privileges, and the vulnerability's remote nature makes it particularly attractive for large-scale attacks. Organizations should immediately update to patched versions of Foxit Reader, implement network-based intrusion detection systems to monitor for exploitation attempts, and conduct user awareness training to reduce the risk of successful social engineering attacks. Additionally, implementing application whitelisting policies and restricting PDF document handling to trusted sources can provide additional layers of protection against this and similar vulnerabilities. The vulnerability highlights the importance of proper input validation and type safety in document processing applications, as these systems often handle untrusted content from external sources and must maintain robust security boundaries to prevent exploitation.