CVE-2018-17690 in PhantomPDF
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 rect property of a Link object. 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-7103.
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Analysis
by VulDB Data Team • 08/01/2024
CVE-2018-17690 represents a critical remote code execution vulnerability affecting Foxit PhantomPDF version 9.2.0.9297, classified under CWE-476 as a NULL Pointer Dereference vulnerability. This flaw resides within the PDF document parsing engine where the application fails to properly validate the existence of objects before attempting operations on them, specifically when processing the rect property of Link objects. The vulnerability stems from insufficient input validation mechanisms that should have verified object existence prior to object manipulation. Attackers can exploit this weakness by crafting malicious PDF documents containing malformed Link objects with invalid rect properties, which when processed by the vulnerable software trigger the NULL pointer dereference condition. The exploitation requires user interaction through either visiting a malicious webpage hosting the crafted PDF or opening the malicious file directly, making this a typical client-side attack vector. This vulnerability operates at the application layer and leverages the principle of improper input validation as outlined in the OWASP Top Ten, specifically targeting the lack of proper object validation before operations. The security implications extend beyond simple code execution as the attacker can leverage this to run arbitrary commands with the privileges of the running process, potentially leading to full system compromise. According to ATT&CK framework, this vulnerability maps to T1059.007 for command and scripting interpreter and T1068 for exploit for privilege escalation. The impact is particularly severe because PDF readers like Foxit PhantomPDF are commonly used in enterprise environments where users frequently open documents from untrusted sources, creating a high-risk attack surface. The vulnerability demonstrates a classic memory safety issue where object references are not properly validated, allowing attackers to manipulate the application's execution flow through carefully crafted PDF content. The ZDI-CAN-7103 reference indicates this vulnerability was tracked by the Zero Day Initiative, highlighting its significance in the cybersecurity community. Organizations using Foxit PhantomPDF should immediately apply vendor patches or implement network-based protections to prevent exploitation attempts. The vulnerability's remote nature and requirement for user interaction make it particularly dangerous in phishing campaigns or compromised websites where users might unknowingly trigger the exploit. Security teams should also implement strict file validation policies and user education programs to reduce the likelihood of successful exploitation attempts.