Currently the http fetcher passes --no-check-certificate to wget, which means any SSL errors are ignored. Whilst we have checksums for validation, this is not a good look and I believe we should remove this option. I removed it locally and did a world fetch to a fresh DL_DIR of oe-core+meta-oe. There were quite a few 404s from meta-oe, but nothing actually failed with SSL errors. I'd like to hope that we can simply remove the option, as any sites that have broken SSL can hopefully be switched to use http: instead.
But at least ignored certificates prevent man-in-the-middle attacks that straight http won't? The real solution is all the upstreams need valid certificates ;)
Good news: world fetch for oe-core+meta-oe resulted in no SSL failures.
As per Joshua Watt: please allow certificate checking to be disabled globally because some companies use MITM edge devices that break wget.
Patch on the list.
Fixed in bitbake 4104850dd36096a9ff01836c5fca9ac0e452bcf8.