CVE-2019-25362: WMV to AVI Converter Buffer Overflow RCE

CVE-2019-25362 Overview

CVE-2019-25362 is a stack-based buffer overflow vulnerability affecting WMV to AVI MPEG DVD WMV Convertor version 4.6.1217. The vulnerability exists in the application's input handling of the license name and license code fields, allowing attackers to execute arbitrary code. By crafting a malicious payload of approximately 6000 bytes, an attacker can exploit this vulnerability to trigger a bind shell on port 4444, achieving full remote code execution on the target system.

Critical Impact

This vulnerability allows attackers to execute arbitrary code with the privileges of the application user, potentially leading to complete system compromise through remote bind shell access.

Affected Products

• WMV to AVI MPEG DVD WMV Convertor 4.6.1217

Discovery Timeline

• 2026-02-18 - CVE CVE-2019-25362 published to NVD
• 2026-02-19 - Last updated in NVD database

Technical Details for CVE-2019-25362

Vulnerability Analysis

This vulnerability is classified as CWE-787 (Out-of-Bounds Write), specifically manifesting as a stack-based buffer overflow in the WMV to AVI MPEG DVD WMV Convertor application. The application fails to properly validate the length of user-supplied input in the license registration fields before copying data to a fixed-size buffer on the stack.

When processing the license name and license code fields, the application allocates a static buffer without implementing adequate bounds checking. An attacker who supplies input exceeding the allocated buffer size can overwrite adjacent stack memory, including the return address and other critical control flow data.

Root Cause

The root cause of this vulnerability is improper input validation in the license registration functionality. The application directly copies user-controlled data from the license name and license code fields into a stack-based buffer without verifying that the input length does not exceed the buffer's capacity. This classic stack buffer overflow pattern allows attackers to corrupt the stack frame and redirect program execution.

Attack Vector

The attack is network-accessible and requires no authentication or user interaction. An attacker can exploit this vulnerability by crafting a specially formed input payload targeting the license registration fields. The attack methodology involves:

1. Creating a payload of approximately 6000 bytes containing shellcode and the appropriate return address overwrite
2. Injecting this payload into the license name or license code field
3. Triggering the buffer overflow to overwrite the return address on the stack
4. Redirecting execution to attacker-controlled shellcode
5. Establishing a bind shell listener on port 4444 for remote access

The vulnerability has been documented in multiple public exploit databases. Technical details and proof-of-concept exploits are available through Exploit-DB #47563 and Exploit-DB #47568.

Detection Methods for CVE-2019-25362

Indicators of Compromise

• Unexpected network connections on port 4444 originating from the WMV Convertor process
• Crash dumps or error logs indicating buffer overflow conditions in the application
• Presence of shellcode patterns in memory during application runtime
• Unusual process spawning from the WMV Convertor executable

Detection Strategies

• Monitor for network bind attempts on port 4444 associated with the WMV Convertor application
• Implement endpoint detection rules to identify buffer overflow exploitation attempts targeting the application
• Deploy memory protection mechanisms such as DEP and ASLR to detect exploitation attempts
• Use application whitelisting to prevent unauthorized code execution from the vulnerable process

Monitoring Recommendations

• Configure network monitoring to alert on unexpected outbound connections from media converter applications
• Enable process monitoring to detect child process creation from WMVConvertor.exe or similar executables
• Review Windows Event Logs for application crashes that may indicate exploitation attempts
• Implement file integrity monitoring on the application directory

How to Mitigate CVE-2019-25362

Immediate Actions Required

• Remove or disable WMV to AVI MPEG DVD WMV Convertor 4.6.1217 from all systems immediately
• Block network access for the vulnerable application using host-based firewall rules
• Audit systems for indicators of compromise, particularly unexpected network listeners on port 4444
• Consider replacing the vulnerable software with a modern, actively maintained alternative

Patch Information

No official patch is currently available from the vendor for this vulnerability. The software appears to be legacy/abandonware. Organizations should evaluate alternative media conversion tools that are actively maintained and receive security updates. Additional information may be available from the vendor's official site or the VulnCheck advisory.

Workarounds

• Uninstall the vulnerable application from all production and workstation systems
• Isolate any systems that must run this software on a segmented network with no outbound internet access
• Run the application in a sandboxed environment or virtual machine if usage is absolutely required
• Implement network egress filtering to block connections on port 4444 from workstations

# Windows Firewall rule to block outbound connections on port 4444
netsh advfirewall firewall add rule name="Block Port 4444 Outbound" dir=out action=block protocol=tcp localport=4444
netsh advfirewall firewall add rule name="Block Port 4444 Inbound" dir=in action=block protocol=tcp localport=4444