#VU56794 Arbitrary file upload in vCenter Server - CVE-2021-22005

Vulnerability identifier: #VU56794

Vulnerability risk: Critical

CVSSv4.0: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:A/U:Red]

CVE-ID: CVE-2021-22005

CWE-ID: CWE-434

Exploitation vector: Network

Exploit availability: Yes

Vulnerable software:
vCenter Server
Server applications / Virtualization software

Vendor: VMware, Inc

Description

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to insufficient validation of file during file upload within the Analytics service. A remote non-authenticated attacker with network access to port 443/TCP can upload and execute arbitrary file on the server.

Successful exploitation of the vulnerability may results in full compromise of the affected system.

Note, we are aware of the vulnerability being exploited in the wild as of September 23.

Mitigation

Install updates from vendor's website.

Note, the vulnerability affects any version of vCenter Server 7.0 and vCenter Server 6.7 running on Virtual Appliance (e.g. vCenter Server 6.7 running on Windows is not affected).

Vulnerable software versions

vCenter Server: 6.7 U3d - 7.0.0

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External links
https://www.vmware.com/security/advisories/VMSA-2021-0020.html
https://kb.vmware.com/s/article/85717

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

Yes. This vulnerability is being exploited in the wild.