CVE-2021-47774: Kingdia CD Extractor RCE Vulnerability

CVE-2021-47774 Overview

CVE-2021-47774 is a buffer overflow vulnerability in Kingdia CD Extractor version 3.0.2 that allows attackers to execute arbitrary code through a maliciously crafted payload in the registration name field. This vulnerability exploits improper input validation, enabling attackers to overwrite the Structured Exception Handler (SEH) and establish a bind shell for remote code execution.

Critical Impact

Successful exploitation of this buffer overflow vulnerability allows attackers to achieve arbitrary code execution on the target system, potentially leading to complete system compromise through bind shell access.

Affected Products

• Kingdia CD Extractor 3.0.2

Discovery Timeline

• 2026-01-15 - CVE-2021-47774 published to NVD
• 2026-01-16 - Last updated in NVD database

Technical Details for CVE-2021-47774

Vulnerability Analysis

This vulnerability is classified as CWE-787 (Out-of-Bounds Write), a type of memory corruption vulnerability that occurs when the application writes data past the boundaries of an allocated memory buffer. In Kingdia CD Extractor 3.0.2, the registration name field fails to properly validate the length of user-supplied input, allowing an attacker to submit more than 256 bytes of data.

When the buffer boundary is exceeded, the excess data overwrites critical memory structures, including the Structured Exception Handler (SEH). The SEH is a Windows mechanism for handling exceptions in applications—by overwriting the SEH chain, an attacker can redirect program execution flow to attacker-controlled code when an exception is triggered.

Root Cause

The root cause of this vulnerability is insufficient bounds checking on the registration name input field. The application allocates a fixed-size buffer (256 bytes) for the registration name but does not validate that user input stays within this boundary before copying the data. This allows attackers to supply input exceeding the buffer size, resulting in a classic stack-based buffer overflow condition.

Attack Vector

The attack requires local access with user interaction—specifically, a victim must enter or paste a malicious registration name into the application. An attacker can craft a payload exceeding 256 bytes that includes shellcode designed to establish a bind shell. The payload must be carefully constructed to:

1. Fill the buffer up to its boundary
2. Overwrite the SEH with a pointer to attacker-controlled code or a pivot gadget
3. Include shellcode that executes when the exception handler is invoked

The exploitation technique leverages SEH overwrite, a classic Windows exploitation method that bypasses basic stack protection mechanisms. Technical details and a proof-of-concept are documented in Exploit-DB #50470.

Detection Methods for CVE-2021-47774

Indicators of Compromise

• Presence of Kingdia CD Extractor 3.0.2 installations on endpoints
• Unusual network connections originating from the kingdia.exe process, particularly bind shell activity
• Crash dumps or exception logs from Kingdia CD Extractor indicating access violations or SEH corruption
• Registry or file artifacts containing unusually long registration name values (>256 bytes)

Detection Strategies

• Deploy endpoint detection rules to monitor for SEH overwrite patterns and suspicious shellcode execution
• Implement application allowlisting to prevent execution of legacy, vulnerable software like Kingdia CD Extractor 3.0.2
• Monitor for anomalous process behavior such as kingdia.exe spawning command shells or establishing network listeners
• Use memory protection tools to detect stack buffer overflow attempts and SEH manipulation

Monitoring Recommendations

• Enable Windows Event Logging for application crashes and access violations to capture exploitation attempts
• Configure SentinelOne behavioral AI to detect post-exploitation activities like bind shell establishment
• Monitor network traffic for unexpected listening ports that may indicate successful bind shell deployment
• Implement file integrity monitoring on application directories to detect tampering or payload staging

How to Mitigate CVE-2021-47774

Immediate Actions Required

• Remove or uninstall Kingdia CD Extractor 3.0.2 from all systems in the environment
• Audit systems for the presence of this legacy software using endpoint management tools
• Block execution of kingdia.exe via application control policies
• Review systems where the application was installed for signs of compromise

Patch Information

No vendor patch is currently available for this vulnerability. Kingdia CD Extractor is legacy software that appears to be abandoned. Users should discontinue use of this application and migrate to actively maintained CD ripping alternatives that receive regular security updates.

Additional product information can be found at the Kingdia CD Extractor Overview.

Workarounds

• Completely remove Kingdia CD Extractor 3.0.2 from all systems as the primary mitigation
• If removal is not immediately possible, restrict the application's network access using host-based firewalls to prevent bind shell communication
• Apply application sandboxing to isolate the vulnerable application from critical system resources
• Disable or restrict user access to the registration functionality within the application if possible