CVE-2017-14458 in Foxit
Summary
by MITRE
An exploitable use-after-free vulnerability exists in the JavaScript engine of Foxit Software's Foxit PDF Reader version 8.3.2.25013. A specially crafted PDF document can trigger a previously freed object in memory to be reused, resulting in arbitrary code execution. An attacker needs to trick the user to open the malicious file to trigger this vulnerability. If the browser plugin extension is enabled, visiting a malicious site can also trigger the vulnerability.
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Analysis
by VulDB Data Team • 03/03/2023
The vulnerability identified as CVE-2017-14458 represents a critical use-after-free flaw within the JavaScript engine of Foxit PDF Reader version 8.3.2.25013, classified under CWE-416 as use of freed memory. This vulnerability stems from improper memory management where the JavaScript engine fails to properly track object references, leading to scenarios where freed memory locations are accessed after being reallocated. The flaw occurs during the processing of specially crafted PDF documents that contain malicious JavaScript code designed to exploit memory corruption patterns inherent in the reader's implementation. The vulnerability's exploitation requires user interaction through opening a malicious PDF file or visiting a malicious website when the browser plugin extension is enabled, making it particularly dangerous in phishing scenarios and drive-by download attacks.
The technical implementation of this vulnerability involves the JavaScript engine's object management system where objects are allocated in memory, processed, and subsequently freed during normal document parsing operations. However, the flaw allows for a situation where JavaScript code can manipulate object references in such a way that a freed object is accessed again, creating a use-after-free condition. This condition can be leveraged by attackers to execute arbitrary code with the privileges of the victim user, as the freed memory location can be overwritten with malicious code pointers or data structures. The vulnerability's exploitation potential is significantly amplified when the browser plugin is enabled, as it provides an additional attack surface through web-based delivery mechanisms, allowing attackers to trigger the vulnerability through web browsers without requiring direct user interaction with PDF files.
The operational impact of CVE-2017-14458 extends beyond simple code execution to encompass complete system compromise, as the vulnerability can be exploited through multiple attack vectors including email attachments, malicious websites, and social engineering campaigns. The attack chain typically begins with an attacker crafting a PDF document containing malicious JavaScript that triggers the memory corruption, followed by delivery through phishing emails, compromised websites, or malicious file sharing platforms. When successfully exploited, the vulnerability allows attackers to bypass security controls, escalate privileges, and potentially establish persistent access to target systems. This vulnerability aligns with ATT&CK technique T1059.007 for JavaScript execution and T1203 for exploitation for execution, representing a significant threat to enterprise security environments where PDF readers are commonly used for document processing and review.
Organizations affected by this vulnerability should implement immediate mitigations including disabling the browser plugin extension when not required, updating to patched versions of Foxit PDF Reader, and implementing email filtering solutions to prevent delivery of malicious PDF attachments. Network-based defenses should include web proxy filtering to block access to known malicious domains and content inspection for PDF files. User awareness training should emphasize the dangers of opening unexpected PDF files and visiting untrusted websites, particularly those containing embedded JavaScript. Security monitoring should focus on detecting unusual JavaScript execution patterns and memory access anomalies that may indicate exploitation attempts. The vulnerability demonstrates the importance of proper memory management in software applications and highlights the critical need for regular security updates and patch management processes to protect against known exploits in widely used software applications.