CVE-2018-17650 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 handling of the resolveNodes method of a TimeField. 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-6487.
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Analysis
by VulDB Data Team • 05/05/2020
CVE-2018-17650 represents a critical remote code execution vulnerability affecting Foxit Reader version 9.2.0.9297, classified under CWE-476 as a NULL Pointer Dereference vulnerability. This weakness occurs within the TimeField class's resolveNodes method where the application fails to validate whether an object reference exists before attempting to perform operations on it. The vulnerability stems from inadequate input validation and object lifecycle management within the PDF processing engine, creating a condition where maliciously crafted PDF documents can trigger unexpected behavior when the affected software attempts to process time-related fields in the document structure.
The exploitation of this vulnerability requires user interaction through either visiting a malicious webpage that loads a compromised PDF or opening a specially crafted malicious file, making it a prime example of a user-initiated attack vector. When a victim interacts with the malicious content, the application's PDF parser encounters the malformed TimeField object and attempts to resolve nodes without proper null checks, leading to memory corruption and potential code execution in the context of the current process. This type of vulnerability aligns with ATT&CK technique T1203, where adversaries leverage application vulnerabilities to execute malicious code through legitimate software interfaces.
The operational impact of this vulnerability extends beyond simple code execution, as it provides attackers with a foothold for further exploitation within the victim's system. Since the vulnerability operates within the context of the Foxit Reader application, successful exploitation could allow attackers to access sensitive documents, exfiltrate data, or establish persistent access through additional attack vectors. The vulnerability's classification as a remote code execution flaw means that attackers can potentially compromise systems without requiring physical access or local network presence, making it particularly dangerous in enterprise environments where PDF documents are frequently shared.
Security mitigations for CVE-2018-17650 should focus on immediate remediation through official patches provided by Foxit Corporation, as well as implementing defensive measures such as PDF sandboxing, restricted user permissions, and network-based controls that prevent access to untrusted PDF content. Organizations should also consider deploying web application firewalls and content filtering solutions that can detect and block malicious PDF files before they reach end users. The vulnerability demonstrates the critical importance of proper object validation in software development practices and serves as a reminder of the potential consequences when applications fail to validate object references before operations are performed, highlighting the need for comprehensive input validation and defensive programming techniques throughout the software development lifecycle.