CVE-2022-42408 in PDF-XChange Editor
Summary
by MITRE • 01/26/2023
This vulnerability allows remote attackers to disclose sensitive information on affected installations of PDF-XChange Editor. 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 EMF files. 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 in conjunction with other vulnerabilities to execute arbitrary code in the context of the current process. Was ZDI-CAN-18543.
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Analysis
by VulDB Data Team • 04/29/2025
CVE-2022-42408 represents a critical information disclosure vulnerability affecting PDF-XChange Editor versions up to 8.0.0.370. This weakness falls under the category of improper validation of pointers or object references, which aligns with CWE-476 and CWE-125. The vulnerability specifically manifests during the processing of Enhanced Metafile (EMF) files, a graphics format commonly used for vector graphics in Windows environments. The flaw occurs when the application fails to validate whether an object exists before attempting to perform operations on it, creating a dangerous condition where memory access violations can occur.
The exploitation scenario requires user interaction, making this a client-side vulnerability that can be delivered through malicious web pages or crafted files. When a user visits an attacker-controlled website or opens a malicious EMF file, the vulnerable parsing logic triggers the information disclosure mechanism. This type of attack vector aligns with the ATT&CK technique T1203 - Exploitation for Client Execution, where adversaries leverage application vulnerabilities to execute code. The vulnerability's impact extends beyond simple information disclosure, as it can be leveraged in combination with other exploits to achieve arbitrary code execution within the context of the current process, representing a significant escalation from the initial disclosure.
From a technical perspective, the vulnerability demonstrates poor defensive programming practices where the application does not implement proper null pointer checks or object validation before dereferencing pointers. This type of flaw is particularly dangerous because it can lead to memory corruption, potentially allowing attackers to extract sensitive data from the application's memory space or manipulate program execution flow. The vulnerability's classification as a remote attack vector means that network-based exploitation is possible without requiring physical access to the target system, making it particularly concerning for enterprise environments where users frequently browse untrusted websites or open attachments from unknown sources.
The operational impact of this vulnerability extends to organizations that rely heavily on PDF-XChange Editor for document management and collaboration. Attackers can exploit this weakness to gain unauthorized access to sensitive information stored in memory or to escalate privileges through code execution. The vulnerability's presence in a widely-used document editing application means that successful exploitation could lead to data breaches, privilege escalation, and potentially full system compromise. Organizations should consider this vulnerability as part of a broader attack surface assessment, particularly when evaluating the security posture of applications that handle untrusted file formats. The remediation approach should include immediate patching of the affected software, implementation of web application firewalls to block malicious content, and user education to avoid visiting suspicious websites or opening untrusted files. Additionally, security teams should monitor for indicators of compromise related to this vulnerability and ensure that their incident response procedures include specific checks for this particular weakness in their software inventory.