Threat Response – vCenter Server 6.5, 6.7, and 7.0 Remote Code Execution Vulnerabilities

26-05-2021

A SAFE DIGITAL JOURNEY

On the 25th of May VMWare published a patch to a critical vulnerability in vCenter Server. This vulnerability affects vCenter Server versions 6.5, 6.7 and 7.0. The vulnerability is tracked as CVE-2021-21985. Additionally, a slightly less serious vulnerability with number CVE-2021-21986 is patched.

Impact
The vulnerabilities CVE-2021-21985 in vCenter Server enables an unauthenticated attacker who has access to port 443 to execute commands with unrestricted privileges. We assess the impact of this vulnerability as high.

Risk
This attack is relatively easy to exploit[2]. Therefore the risk of an attacker exploiting this vulnerability is high.

Mitigation
VMware provided a patch to resolve the listed vulnerabilities, and advises to perform an emergency patch as quickly as possible. A workaround/mitigation is available: marking specific plugins in vCenter as incompatible [1]. VMware advises against this, as it disables certain vSAN-functionality.

What does Northwave do?
Northwave is investigating the possibilities for monitoring exploitation attempts of this vulnerability, and will implement detection rules when possible.
Northwave will monitor any developments regarding this vulnerability. If new critical information about this threat arises we will reach out to you. If you need additional information you can call us by phone or send us an email.

Phone number: +31 (0)30-303 1244 (during business hours)
E-mail: [email protected]
Do you have an incident right now? Call our CERT number: +31 (0)85-0437 909 or 0800-1744 (alleen vanuit Nederland)

Disclaimer applies, see below.

Sources

[1]: https://blogs.vmware.com/vsphere/2021/05/vmsa-2021-0010.html
[2]: https://www.bleepingcomputer.com/news/security/vmware-warns-of-critical-bug-affecting-all-vcenter-server-installs/

 

Disclaimer
Northwave has made every effort to make this information accurate and reliable. However, the information provided is without warranty of any kind and its use is at the sole risk of the user. Northwave does not accept any responsibility or liability for the accuracy, content, completeness, legality or reliability of the information provided. We shall not be liable for any loss or damage of whatever nature, direct or indirect, consequential or other, whether arising in contract, tort or otherwise, which may arise as a result of your use of, or inability to use, this information or any additional information provided by us in direct or indirect relation to the information provided here.