CVE-2018-1176 in Foxit
Summary
by MITRE
This vulnerability allows remote attackers to execute arbitrary code on vulnerable installations of Foxit Reader 9.0.0.29935. 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 parsing of ePub files. The issue results from the lack of proper validation of user-supplied data, which can result in a write past the end of an allocated object. An attacker can leverage this vulnerability to execute code under the context of the current process. Was ZDI-CAN-5442.
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Analysis
by VulDB Data Team • 02/06/2020
The vulnerability identified as CVE-2018-1176 represents a critical remote code execution flaw in Foxit Reader version 9.0.0.29935 that demonstrates a classic buffer overflow condition within the ePub file parsing functionality. This vulnerability operates under the Common Weakness Enumeration category CWE-121, which encompasses stack-based buffer overflow conditions that occur when a program writes past the end of a fixed-length buffer. The flaw specifically manifests during the processing of ePub documents, which are widely used digital publishing formats that combine html content with xml metadata and other resources. The vulnerability requires user interaction to exploit, meaning that an attacker must entice a victim to visit a malicious webpage or open a crafted malicious ePub file, making this a typical client-side attack vector that relies on social engineering elements.
The technical implementation of this vulnerability stems from inadequate input validation during the parsing of ePub file structures, particularly in how the software handles user-supplied data within the document metadata or content sections. When Foxit Reader processes an ePub file, it fails to properly validate the size and boundaries of data structures, allowing an attacker to craft a malicious file that contains oversized or malformed data elements. This insufficient validation creates a condition where memory allocation occurs based on seemingly legitimate data, but the actual processing exceeds the allocated buffer boundaries, resulting in a write past the end of an allocated object. The consequence of this flaw is that arbitrary code execution becomes possible within the context of the current process, effectively allowing an attacker to execute malicious code with the same privileges as the Foxit Reader application itself.
The operational impact of this vulnerability extends beyond simple remote code execution, as it creates a significant threat vector for attackers seeking to compromise systems through targeted attacks against vulnerable Foxit Reader installations. The vulnerability's requirement for user interaction does not diminish its severity, as it can be effectively exploited through phishing campaigns, malicious websites, or compromised documents distributed through various attack vectors. Security researchers have noted that this flaw aligns with the MITRE ATT&CK framework's technique T1203, which covers exploitation for execution through web-based attacks, and T1059, which involves command and scripting interpreter usage. The attack surface is particularly concerning given that Foxit Reader is widely deployed in enterprise environments, making the potential impact of successful exploitation significant for organizations that rely on this software for document viewing and processing.
Mitigation strategies for CVE-2018-1176 should focus on immediate software updates and patches provided by Foxit Corporation, as well as implementing defensive measures such as web application firewalls and content filtering systems that can detect and block malicious ePub files. Organizations should also consider restricting user access to potentially malicious websites and implementing email filtering solutions that can identify suspicious file attachments. The vulnerability demonstrates the importance of proper input validation and memory safety practices in document processing software, aligning with security best practices outlined in standards such as the OWASP Top Ten and the CERT Secure Coding Standards. Additionally, security teams should implement monitoring solutions that can detect unusual process execution patterns that might indicate exploitation attempts, and conduct regular vulnerability assessments to identify other potential attack vectors within the document processing ecosystem.