CVE-2018-17679 in Foxit
Summary
by MITRE
This vulnerability allows remote attackers to execute arbitrary code on vulnerable installations of Foxit Reader 9.2.0.9297. 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 parsing of PDF documents. By manipulating a document's elements, an attacker can cause a pointer to be reused after it has been freed. An attacker can leverage this vulnerability to execute code in the context of the current process. Was ZDI-CAN-6890.
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Analysis
by VulDB Data Team • 08/01/2024
This vulnerability in Foxit Reader 9.2.0.9297 represents a critical heap-based buffer overflow condition that arises during PDF document parsing operations. The flaw stems from improper memory management within the application's PDF parser, specifically when handling certain document elements that trigger a use-after-free condition. The vulnerability is classified as a CWE-416: Use After Free, which occurs when a program continues to reference memory after it has been freed, creating opportunities for arbitrary code execution. Attackers can exploit this by crafting malicious PDF documents that contain specially constructed elements designed to manipulate the memory allocation and deallocation process within the Foxit Reader application.
The exploitation mechanism relies on a remote attacker crafting a malicious PDF file that, when opened or viewed by a victim using the vulnerable version of Foxit Reader, triggers the flawed memory handling routine. This requires user interaction through either visiting a malicious webpage that hosts the PDF or opening the malicious file directly. The technical implementation involves manipulating PDF objects and their associated memory pointers in such a way that when the parser attempts to process these elements, it reuses a pointer that has already been freed, leading to unpredictable behavior and potential code execution. The vulnerability exists at the intersection of memory safety issues and application security flaws, making it particularly dangerous in enterprise environments where PDF documents are frequently exchanged.
The operational impact of this vulnerability extends beyond simple code execution, as it allows attackers to operate within the security context of the currently running Foxit Reader process. This means that any privileges the application has are effectively transferred to the attacker, potentially enabling access to sensitive documents, system resources, or even lateral movement within a network. The vulnerability's classification under the ZDI-CAN-6890 identifier indicates it was recognized by the Zero Day Initiative as a significant security concern requiring immediate attention. From an adversary perspective, this vulnerability fits well within the ATT&CK framework's technique T1203: Exploitation for Client Execution, as it leverages a client-side application vulnerability to achieve remote code execution.
Organizations using Foxit Reader should immediately implement mitigations including updating to the patched version of the software, implementing network-based restrictions on PDF file downloads, and deploying application whitelisting policies that prevent execution of untrusted PDF files. Additionally, security teams should consider implementing sandboxing techniques for PDF processing and monitoring for suspicious PDF file patterns. The vulnerability highlights the importance of proper memory management in document processing applications and serves as a reminder of the critical need for regular security updates. Network administrators should also consider implementing web application firewalls that can detect and block malicious PDF content, while endpoint protection solutions should be configured to scan PDF files for potential exploitation indicators. This vulnerability demonstrates how seemingly routine document processing operations can become attack vectors when memory safety is not properly enforced, making it essential for security professionals to maintain vigilance against such flaws in widely used applications.