Published: October 26, 2023
Overview
A critical vulnerability has been identified in VMware’s vCenter Server. The vulnerability, CVE-2023-34048, is an out-of-bounds write vulnerability in the implementation of the DCE/RPC protocol. It has a high severity rating with a maximum CVSSv3 base score of 9.8, indicating the potential impact is significant. If exploited, it could allow a malicious actor with network access to execute remote code on the vCenter Server, potentially gaining control over the affected system.
Impact
The impact of the CVE-2023-34048 vulnerability in VMware’s vCenter Server is quite significant due to its critical severity rating. The most concerning impact of this vulnerability is that it allows for remote code execution. A malicious actor with network access to the vCenter Server could potentially trigger an out-of-bounds write, leading to the execution of arbitrary code. In other words, an attacker could potentially take control of the affected system.
Successful exploitation of this vulnerability could allow access to sensitive information, modification of system data, or disruption of the services provided by the system. Each has a high impact on the confidentiality, integrity, and availability of the affected systems.
As of now, there are no known instances of this vulnerability being exploited in the wild. However, given its potential impact, it’s highly recommended for all affected systems to be updated promptly.
Applicable Versions
| Affected Version | Updated Version |
|---|---|
| VMware vCenter Server 8.0 | 8.0U1d or 8.0U2 |
| VMware vCenter Server 7.0 | 7.0U3o |
| VMware Cloud Foundation 5.x and 4.x | Security Updates for 5.x and 4.x |
Mitigations and Workarounds
There are no workarounds for this vulnerability. Apply the following actions to prevent exploitation of the vulnerability:
- Update the security updates released by VMWare immediately to mitigate any potential threats.
- Due to the critical severity of this vulnerability and lack of workaround, VMware has made a patch generally available for vCenter Server 6.7U3, 6.5U3, and VCF 3.x. Asynchronous vCenter Server patches for VCF 5.x and 4.x deployments are also available.
These updates and patches should be applied immediately to mitigate any potential threats.
Best Practices
Here are some best practices to mitigate and prevent the exploitation of the CVE-2023-34048 vulnerability in VMware’s vCenter Server:
- The primary mitigation for this vulnerability is to apply the updates provided by VMware. It’s crucial for organizations to apply these patches as soon as possible to protect their systems.
- Use security tools, such as endpoint detection and response (EDR), web application firewalls, and network protocol analyzers. These tools can help detect and prevent potential exploits.
- Follow VMware’s vSphere Security Configuration & Hardening Guides. These guides provide baseline hardening guidance for VMware vSphere, including in-guest Tools configurations to limit host-to-guest interaction.
Remember, the best defense against vulnerabilities is a proactive approach to security. Regularly updating and patching software, using security tools, and following security best practices can significantly reduce the risk of exploitation.
Netsurion Detection and Response
Netsurion researchers are continuously monitoring the exploits of this vulnerability. Our security analysts will add the IOCs (Indicators of Compromise – the hashes of malicious files and the IP addresses) to Netsurion Threat Center, our threat intelligence platform. This will help detect malicious files and suspicious Command and Control communications to malicious IP addresses to detect the exploitation of this vulnerability. Netsurion’s vulnerability management system will also detect the vulnerability (CVE-2023-34048) for customers who have subscribed to Netsurion Vulnerability Management.
References:
- https://www.vmware.com/security/advisories/VMSA-2023-0023.html
- https://kb.vmware.com/s/article/88287
- https://www.helpnetsecurity.com/2023/10/25/cve-2023-34048/
- https://thehackernews.com/2023/10/act-now-vmware-releases-patch-for.html
- https://www.bleepingcomputer.com/news/security/vmware-fixes-critical-code-execution-flaw-in-vcenter-server/
- https://www.opencve.io/cve/CVE-2023-34048
- https://securityonline.info/cve-2023-34048-critical-vmware-vcenter-server-flaw-allows-remote-code-execution/