CVE-2017-16585 in Foxit
Summary
by MITRE
This vulnerability allows remote attackers to execute arbitrary code on vulnerable installations of Foxit Reader 8.3.2.25013. 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 app.response method. 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-5294.
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Analysis
by VulDB Data Team • 12/16/2019
This vulnerability in Foxit Reader 8.3.2.25013 represents a critical remote code execution flaw that demonstrates poor input validation practices within the application's response handling mechanism. The vulnerability specifically resides in the app.response method where the software fails to properly validate whether an object exists before attempting to perform operations on it. This type of error falls under the common weakness identified as CWE-476, which describes NULL Pointer Dereference conditions that occur when a program attempts to access a null pointer as if it were a valid object reference. The flaw creates a dangerous condition where attacker-controlled data can manipulate the application's execution flow and potentially lead to arbitrary code execution on the target system.
The exploitation of this vulnerability requires user interaction through either visiting a malicious webpage or opening a specially crafted malicious file, making it a prime example of a client-side attack vector. This approach aligns with the attack techniques documented in the MITRE ATT&CK framework under the T1203 category for Exploitation for Client Execution, where adversaries leverage vulnerabilities in client applications to execute malicious code. The attack chain begins with the delivery of malicious content to the victim, followed by the user's interaction with the compromised file or webpage, which then triggers the vulnerable code path within Foxit Reader's response handling method.
The operational impact of this vulnerability extends beyond simple code execution, as the attacker can leverage the vulnerability to execute code under the context of the current process, effectively compromising the user's system. This privilege escalation capability means that the malicious code runs with the same permissions as the Foxit Reader application, potentially allowing access to sensitive documents, system resources, or the ability to perform further attacks on the local network. The vulnerability's classification as a remote code execution flaw makes it particularly dangerous in enterprise environments where users may inadvertently encounter malicious content through email attachments, web browsing, or document sharing platforms.
Security professionals should recognize this vulnerability as a classic example of insufficient input validation that can be addressed through proper defensive programming practices. The recommended mitigations include implementing comprehensive object existence checks before performing operations on potentially untrusted data, applying the principle of least privilege to limit the impact of successful exploitation, and maintaining up-to-date software versions to avoid known vulnerabilities. Organizations should also consider deploying network-based intrusion detection systems to monitor for suspicious traffic patterns associated with exploitation attempts, as well as implementing user education programs to reduce the risk of successful social engineering attacks that deliver malicious payloads to vulnerable systems. The vulnerability serves as a reminder of the importance of defensive coding practices and the need for regular security assessments to identify and remediate similar issues in software applications.