CVE-2025-6649 in PDF-XChange
Summary
by MITRE • 06/26/2025
PDF-XChange Editor U3D File Parsing Out-Of-Bounds Read Information Disclosure Vulnerability. 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 U3D files. The issue results from the lack of proper validation of user-supplied data, which can result in a read past the end of an allocated buffer. An attacker can leverage this in conjunction with other vulnerabilities to execute arbitrary code in the context of the current process. Was ZDI-CAN-26709.
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Analysis
by VulDB Data Team • 07/02/2025
The CVE-2025-6649 vulnerability represents a critical out-of-bounds read flaw within PDF-XChange Editor's handling of U3D files, a three-dimensional file format commonly used in technical documentation and engineering drawings. This vulnerability falls under the CWE-125 category of out-of-bounds read conditions, where the software fails to properly validate input data before processing. The flaw specifically manifests during the parsing phase of U3D file structures, where the application attempts to read memory locations beyond the boundaries of allocated buffer space. This type of vulnerability is particularly dangerous because it can lead to information disclosure, potentially exposing sensitive data from adjacent memory regions including credentials, system information, or other confidential data stored in memory.
The exploitation of this vulnerability requires user interaction, making it a client-side attack vector that typically involves social engineering or phishing campaigns. An attacker must convince a victim to either visit a malicious webpage that automatically triggers the vulnerable U3D parsing routine or to open a specially crafted U3D file within the PDF-XChange Editor application. The attack scenario aligns with ATT&CK technique T1203, where adversaries leverage application vulnerabilities to gain access to system resources. When a victim interacts with the malicious content, the application's insufficient input validation causes it to read beyond allocated memory boundaries, potentially exposing memory contents to the attacker. This information disclosure can include sensitive data from the application's memory space, which may contain authentication tokens, configuration details, or other system information that could be leveraged for further attacks.
The operational impact of this vulnerability extends beyond simple information disclosure, as it can serve as a precursor to more severe exploitation techniques. While the immediate effect is data exposure, the out-of-bounds read condition creates opportunities for attackers to gain insights into memory layout patterns, which can be used to refine subsequent attacks. The vulnerability's potential for arbitrary code execution in the context of the current process makes it particularly concerning for enterprise environments where PDF-XChange Editor is widely deployed. Organizations using this software are at risk of having their systems compromised through indirect exploitation pathways, where the information disclosure serves as a foothold for more sophisticated attacks. This vulnerability particularly affects environments where users frequently interact with technical documentation containing embedded U3D objects, creating numerous potential attack vectors across various industry sectors including engineering, manufacturing, and construction.
Mitigation strategies for CVE-2025-6649 should focus on both immediate protective measures and long-term security improvements. Organizations should prioritize updating to the latest version of PDF-XChange Editor that contains patches addressing this specific out-of-bounds read vulnerability. System administrators should implement network-level controls to block or filter U3D file content where possible, particularly in environments where such files are not essential to business operations. The implementation of application whitelisting policies can help prevent execution of unauthorized versions of the software. Additionally, security monitoring should be enhanced to detect unusual memory access patterns or information disclosure attempts that might indicate exploitation attempts. Regular security assessments should include testing for similar buffer overflow and out-of-bounds read vulnerabilities across all document processing applications. The vulnerability demonstrates the importance of proper input validation and boundary checking in software development practices, aligning with secure coding guidelines that emphasize defensive programming techniques to prevent memory corruption vulnerabilities. Organizations should also consider implementing sandboxing mechanisms for document processing to limit the potential impact of successful exploitation attempts.