CVE-2019-25670: River Past Video Cleaner SEH Overflow

CVE-2019-25670 Overview

River Past Video Cleaner 7.6.3 contains a structured exception handler (SEH) buffer overflow vulnerability that allows local attackers to execute arbitrary code. The vulnerability exists in the Lame_enc.dll field handling, where a malicious string can be supplied to trigger a buffer overflow condition. Attackers can craft a payload consisting of 280 bytes of padding, a next structured exception handler override, and shellcode to achieve code execution when the application processes the input.

Critical Impact

Local attackers can achieve arbitrary code execution through a structured exception handler buffer overflow, potentially gaining complete control of the affected system.

Affected Products

• River Past Video Cleaner version 7.6.3

Discovery Timeline

• 2026-04-05 - CVE CVE-2019-25670 published to NVD
• 2026-04-07 - Last updated in NVD database

Technical Details for CVE-2019-25670

Vulnerability Analysis

This vulnerability is classified as CWE-787 (Out-of-bounds Write), a memory corruption issue that occurs when the application writes data beyond the boundaries of an allocated buffer. The flaw resides in how River Past Video Cleaner 7.6.3 processes input strings in the Lame_enc.dll field without proper bounds checking.

When a user supplies a specially crafted string exceeding the expected buffer size, the application fails to validate the input length before copying it to a fixed-size buffer. This allows an attacker to overwrite adjacent memory, including the structured exception handler (SEH) chain stored on the stack.

Root Cause

The root cause is improper input validation in the Lame_enc.dll field handler. The application does not enforce boundary checks on user-supplied input, allowing data to overflow the allocated buffer. This is a classic stack-based buffer overflow that specifically targets the SEH chain, a Windows exception handling mechanism that stores function pointers on the stack.

Attack Vector

The attack requires local access to the system where River Past Video Cleaner is installed. An attacker crafts a malicious input string containing:

1. 280 bytes of padding - fills the buffer and reaches the SEH structure
2. SEH override - overwrites the next structured exception handler pointer with a controlled address
3. Shellcode - arbitrary code to execute upon exception handling

When the application triggers an exception (caused by the overflow itself), Windows follows the SEH chain to find an exception handler. Since the attacker has overwritten the handler address, execution is redirected to attacker-controlled code. Technical details and proof-of-concept information are available in the Exploit-DB #46346 entry.

Detection Methods for CVE-2019-25670

Indicators of Compromise

• Unexpected crashes or exceptions in the River Past Video Cleaner application
• Presence of abnormally large or unusual strings in application configuration files or input fields
• Suspicious process behavior spawned from River Past Video Cleaner processes

Detection Strategies

• Monitor for stack-based buffer overflow exploitation attempts targeting video processing applications
• Implement application whitelisting to prevent unauthorized code execution
• Deploy endpoint detection and response (EDR) solutions that can detect SEH overwrite attempts
• Enable Windows Defender Exploit Guard or similar exploit mitigation technologies

Monitoring Recommendations

• Configure logging for application crashes and exceptions in River Past Video Cleaner
• Monitor process execution chains for unusual child processes spawned from the application
• Implement file integrity monitoring on application directories

How to Mitigate CVE-2019-25670

Immediate Actions Required

• Consider uninstalling or replacing River Past Video Cleaner 7.6.3 with alternative software
• Restrict access to the application to trusted users only
• Enable Data Execution Prevention (DEP) and Address Space Layout Randomization (ASLR) system-wide
• Deploy endpoint protection solutions with exploit mitigation capabilities

Patch Information

No vendor patch information is currently available for this vulnerability. River Past Video Cleaner appears to be legacy software. Organizations should evaluate whether continued use of this application is necessary and consider migration to actively maintained alternatives. For additional context, see the VulnCheck Advisory on Buffer Overflow.

Workarounds

• Run the application in a sandboxed or isolated environment to limit potential impact
• Implement strict access controls to prevent untrusted users from interacting with the application
• Deploy Windows exploit mitigation features such as Structured Exception Handling Overwrite Protection (SEHOP)
• Consider using application-level firewalls or security tools to monitor and restrict application behavior