VMware vSphere 7.0 U3c is released today, this version can resolve some critical issues. Please check the followings.
For Log4j issue on vCenter 7.0, vCenter 7.0 U3c can resolve this issue.

https://www.vmware.com/security/advisories/VMSA-2021-0028.html
vSphere 7.0 Update 3 Critical Known Issues
