CVE-2018-9969 in Foxit
Summary
by MITRE
This vulnerability allows remote attackers to execute arbitrary code on vulnerable installations of Foxit Reader 9.0.1.1049. 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 XFA boundItem method of Button elements. The issue results from the lack of validating the existence of an object prior to performing operations on the object. An attacker can leverage this vulnerability to execute code under the context of the current process. Was ZDI-CAN-5579.
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Analysis
by VulDB Data Team • 08/15/2024
CVE-2018-9969 represents a critical remote code execution vulnerability affecting Foxit Reader version 9.0.1.1049, classified under CWE-476 as a null pointer dereference vulnerability. This flaw exists within the XFA (XML Forms Architecture) processing engine, specifically within the boundItem method of Button elements, where the software fails to validate object existence before performing operations on it. The vulnerability stems from insufficient input validation mechanisms that allow maliciously crafted PDF documents to trigger improper memory access patterns. Attackers can exploit this weakness by crafting malicious XFA forms that manipulate Button elements, causing the application to attempt operations on null or uninitialized objects, which ultimately leads to arbitrary code execution. The vulnerability requires user interaction to be exploited, meaning a victim must either visit a malicious web page hosting the exploit or open a maliciously crafted PDF file containing the malicious XFA content. This attack vector aligns with ATT&CK technique T1203, where adversaries leverage application vulnerabilities to execute code remotely. The impact of this vulnerability extends beyond simple code execution as it allows attackers to operate within the context of the current process, potentially escalating privileges or accessing sensitive system resources. The exploitation process typically involves constructing a PDF document with malicious XFA data that when processed by Foxit Reader triggers the null pointer dereference, leading to memory corruption and code execution. This vulnerability particularly affects enterprise environments where Foxit Reader is widely deployed for document processing, making it an attractive target for attackers seeking persistent access to corporate networks. The lack of proper bounds checking and object validation in the XFA processing pipeline creates a dangerous attack surface that can be leveraged for sophisticated attacks including privilege escalation, data exfiltration, or establishment of persistent backdoors. Organizations using Foxit Reader should prioritize immediate patching and implement network segmentation controls to limit exposure to potentially malicious PDF content. The vulnerability demonstrates the critical importance of input validation and proper memory management in document processing applications, as similar issues have been documented in other PDF viewers and office applications. Security professionals should monitor for exploitation attempts targeting this vulnerability and implement appropriate network-based and host-based detection measures to identify and block malicious PDF content before it can be processed by vulnerable applications. The ZDI-CAN-5579 identifier confirms this vulnerability was recognized and tracked by the Zero Day Initiative, highlighting its significance in the cybersecurity community and the need for immediate remediation efforts across affected deployments.