$ git clone -n https://src.fedoraproject.org/rpms/libtommath.git /var/lib/mock/f39-build-1470326-33888/root/chroot_tmpdir/scmroot/libtommath
Cloning into '/var/lib/mock/f39-build-1470326-33888/root/chroot_tmpdir/scmroot/libtommath'...
$ git fetch origin 5079f5a52adaaeed56cb89562f78d0b1488e5d1b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libtommath
 * [new ref]         5079f5a52adaaeed56cb89562f78d0b1488e5d1b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 5079f5a Fix CVE-2023-36328 (#2236877,#2236878)