This package: python-pyABF-2.3.6-2.fc38 ( https://koji.fedoraproject.org/koji/buildinfo?buildID=2067454 )

Causes createrepo_c to output:

C_CREATEREPOLIB: Critical: Cannot dump XML for python3-pyABF (3ab9a1aafc8cc037c279fad85f5d34726a4491f763871b80df494aa9f2856e14): Forbidden control chars found (ASCII values <32 except 9, 10 and 13).
17:15:51: CACHE HIT python3-pyasn1-modules-0.4.8-11.fc37.noarch.rpm

The only thing that looks at all out of the ordinary is a changelog entry:

• added patch [2009cd568066b5ff8d6079e2d8cf8af388066cc9b79