Quoting Brian E. Lavender (brian(a)brie.com):
There are probably a boat load of known
vulnerabilities in F13.
The only way running Internet-exposed Fedora 13, even for a minimal host
that's just barely enough of an OS build to support a hypervisor, in
2022, would involve the local sysadmin _completely_ having assumed and
diligently carried out, without fail, all security maintenance
_manually_ for all eleven years, since 2011-06-24, when Security Team
coverage of F13 ceased permanently.
That would mean diligently reading all CVEs for all local components
exposed to public traffic -- including the Linux kernel (especially its
network stack), all public-facing services, and all of their libs and
support utilities -- doing, as appropriate, paring of
code/functionality, upgrading, mitigating, applying needed source
patches, etc.
That could be done, by a sufficiently determined and well-prepared
sysadmin who wishes to hand-maintain a very minimal system for
locally-compelling reasons. Gary, _did_ you do all that?
If you didn't, Gary, that's likely a key part of your problem. And
dismissing the problem of need to plug proven security holes with "the
upgrade treadmill is that it is a waste of time" is a reminder that
denial isn't a river in Egypt.