A local buffer overflow vulnerability in Rttsoftware PDF Explorer 1.5.66.2 allows an attacker to achieve arbitrary code execution by injecting malicious data into the application interface.

This vulnerability is a structured exception handler (SEH) overflow (CWE-787) triggered when the application processes specially crafted input within the Label field of the Custom fields settings dialog. The attack is initiated by a local, unauthenticated user who provides malicious data to the vulnerable input field.

Successful exploitation of this flaw allows a local attacker to execute arbitrary code with the privileges of the application process. This could lead to full system compromise, unauthorized data access, or the installation of persistent malicious software. Given the CVSS score of 8.4, this vulnerability represents a high risk to organizational security, particularly in multi-user environments where local access is shared.

Immediate Action: Upgrade to the latest version of PDF Explorer if a patch is provided by Rttsoftware. If no update is available, restrict access to the application and monitor the system for unauthorized process execution.

Proactive Monitoring: Review system logs for abnormal application crashes, particularly those occurring after modifications to settings or configuration files. Monitor for the execution of unexpected child processes originating from the PDF Explorer executable.

Compensating Controls: Since this is a local attack, implement strict host-based access controls to limit the number of users who can interact with the application. Ensure that the principle of least privilege is applied to all user accounts on the host system to minimize the impact of a potential code execution event.

Public Exploit Available: Yes — a public proof-of-concept exists, attributed to the technical write-up provided by Exploit-DB (EDB-ID 46016).

This vulnerability presents a significant risk to local system integrity. Administrators should immediately identify and update all instances of PDF Explorer 1.5.66.2 to a secure version. In environments where immediate patching is not feasible, restrict application access to authorized personnel only to mitigate the risk of local exploitation.