CVE-2019-13123 in Foxit
Summary
by MITRE
Foxit Reader 9.6.0.25114 and earlier has two unique RecursiveCall bugs involving 3 functions exhausting available stack memory because of Uncontrolled Recursion in the V8 JavaScript engine (issue 1 of 2).
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 09/17/2020
The vulnerability identified as CVE-2019-13123 represents a critical stack exhaustion issue affecting Foxit Reader versions 9.6.0.25114 and earlier. This flaw resides within the V8 JavaScript engine implementation that Foxit Reader employs for processing PDF documents containing embedded JavaScript code. The vulnerability manifests through two distinct recursive call patterns that exploit uncontrolled recursion mechanisms, leading to rapid stack memory consumption and eventual system instability. The technical nature of this vulnerability aligns with CWE-674, which specifically addresses Uncontrolled Recursion in software implementations.
The core technical flaw involves three specific functions that exhibit recursive behavior without proper termination conditions or stack depth limitations. When malicious PDF documents containing crafted JavaScript code are processed by Foxit Reader, these functions can call themselves repeatedly without bounds, consuming available stack memory until system resources are exhausted. This recursive exhaustion occurs during the parsing and execution phases of PDF JavaScript processing, making the vulnerability particularly dangerous as it can be triggered simply by opening a malicious document. The V8 engine's lack of adequate recursion depth checking mechanisms in the affected Foxit Reader versions creates an ideal environment for this exploit to succeed.
Operationally, this vulnerability presents a significant risk to end users and organizations relying on Foxit Reader for document processing. Attackers can craft malicious PDF files that, when opened in vulnerable versions, will trigger the recursive calls and cause system crashes or potential system hangs. The impact extends beyond simple application instability as this type of vulnerability can serve as a vector for more sophisticated attacks, potentially leading to privilege escalation or code execution in certain scenarios. The vulnerability is particularly concerning in enterprise environments where users frequently open PDF documents from untrusted sources, making it a prime target for social engineering attacks. According to ATT&CK framework, this vulnerability maps to T1203 - Exploitation for Client Execution, as it enables adversaries to execute malicious code through compromised PDF readers.
The mitigation strategies for CVE-2019-13123 primarily focus on immediate software updates and version management. Users should upgrade to Foxit Reader version 10.0.0.35037 or later, which includes patches addressing the recursive call issues in the V8 JavaScript engine. Organizations should implement comprehensive patch management policies to ensure all systems running Foxit Reader are updated promptly. Additionally, implementing PDF document scanning and filtering mechanisms can provide an additional layer of protection by identifying and quarantining potentially malicious documents before they reach end users. Network administrators should consider implementing sandboxing techniques for PDF processing and monitoring for unusual memory consumption patterns that might indicate exploitation attempts. The vulnerability demonstrates the importance of proper recursion handling in interpreted environments and highlights the need for robust input validation and resource limiting mechanisms in software applications that process untrusted data.