hw/pci/pci.c in QEMU 4.2.0 allows guest OS users to trigger an out-of-bounds access by providing an address near the end of the PCI configuration space.
https://www.openwall.com/lists/oss-security/2020/06/04/1
https://security.netapp.com/advisory/ntap-20200717-0001/
https://security.gentoo.org/glsa/202011-09
https://lists.gnu.org/archive/html/qemu-devel/2020-06/msg00706.html