CVE-2018-17698 in Foxit
Summary
by MITRE
This vulnerability allows remote attackers to execute arbitrary code on vulnerable installations of Foxit PhantomPDF 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 handling of the richValue property of a text field. 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 in the context of the current process. Was ZDI-CAN-7067.
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Analysis
by VulDB Data Team • 08/01/2024
CVE-2018-17698 represents a critical buffer overflow vulnerability in Foxit PhantomPDF version 9.2.0.9297 that demonstrates a classic improper input validation flaw categorized under CWE-125. This vulnerability resides within the richValue property handling of text fields within the PDF rendering engine, where the application fails to validate whether an object exists before attempting to perform operations on it. The flaw constitutes a remote code execution vulnerability that requires user interaction through visiting a malicious webpage or opening a specially crafted malicious PDF file. The vulnerability stems from inadequate bounds checking and object validation mechanisms within the PDF parser, specifically when processing rich text formatting properties that are commonly used in PDF forms and annotations. Attackers can exploit this by crafting malicious PDF documents that trigger the vulnerable code path when the PDF viewer attempts to render or process the richValue property of text fields, leading to memory corruption and potential arbitrary code execution within the context of the current process. This vulnerability directly impacts the principle of least privilege and input sanitization as defined in the OWASP Top Ten, where improper validation of input allows for privilege escalation and code execution. The exploitation process typically involves crafting a PDF file with malicious richValue data that triggers a buffer overflow when the application attempts to process the text field properties. The vulnerability affects the PDF rendering engine's ability to properly handle malformed or malicious input data, creating a dangerous condition where attacker-controlled data can overwrite memory locations and potentially redirect execution flow. From an operational perspective, this vulnerability poses significant risk to organizations relying on Foxit PhantomPDF for document processing, as it allows remote attackers to gain execution privileges without requiring local system access. The vulnerability aligns with ATT&CK technique T1059.007 for command and scripting interpreter, specifically through the use of malicious PDF documents to execute arbitrary code. Organizations should implement immediate mitigations including disabling PDF viewing capabilities for untrusted sources, applying vendor patches when available, and implementing network-based protections such as web application firewalls to block malicious PDF content. The vulnerability also highlights the importance of proper object lifecycle management and input validation practices as outlined in the CERT Secure Coding Standards, particularly in preventing use-after-free and buffer overflow conditions. This flaw demonstrates how seemingly benign PDF formatting properties can become attack vectors when proper validation mechanisms are absent, emphasizing the need for comprehensive security testing of document processing libraries and the importance of adhering to secure coding practices throughout the software development lifecycle. The vulnerability's impact extends beyond individual user systems to enterprise environments where PDF documents are frequently shared and processed, making it particularly dangerous in corporate settings where document automation and processing are common.