xmlParseBalancedChunkMemoryRecover in parser.c in libxml2 before 2.9.10 has a memory leak related to newDoc->oldNs.
https://www.oracle.com/security-alerts/cpujul2020.html
https://usn.ubuntu.com/4274-1/
https://us-cert.cisa.gov/ics/advisories/icsa-21-103-08
https://security.netapp.com/advisory/ntap-20200114-0002/
https://lists.debian.org/debian-lts-announce/2020/09/msg00009.html
https://lists.debian.org/debian-lts-announce/2019/12/msg00032.html
https://gitlab.gnome.org/GNOME/libxml2/commit/5a02583c7e683896d84878bd90641d8d9b0d0549
https://cert-portal.siemens.com/productcert/pdf/ssa-292794.pdf
http://lists.opensuse.org/opensuse-security-announce/2020-06/msg00005.html
http://lists.opensuse.org/opensuse-security-announce/2020-05/msg00047.html