The inflateMark function in inflate.c in zlib 1.2.8 might allow context-dependent attackers to have unspecified impact via vectors involving left shifts of negative integers.
https://www.oracle.com/security-alerts/cpujul2020.html
https://wiki.mozilla.org/images/0/09/Zlib-report.pdf
https://wiki.mozilla.org/MOSS/Secure_Open_Source/Completed#zlib
https://usn.ubuntu.com/4292-1/
https://usn.ubuntu.com/4246-1/
https://support.apple.com/HT208144
https://support.apple.com/HT208115
https://support.apple.com/HT208113
https://support.apple.com/HT208112
https://security.gentoo.org/glsa/202007-54
https://security.gentoo.org/glsa/201701-56
https://lists.debian.org/debian-lts-announce/2020/01/msg00030.html
https://lists.debian.org/debian-lts-announce/2019/03/msg00027.html
https://github.com/madler/zlib/commit/e54e1299404101a5a9d0cf5e45512b543967f958
https://bugzilla.redhat.com/show_bug.cgi?id=1402348
https://access.redhat.com/errata/RHSA-2017:3453
https://access.redhat.com/errata/RHSA-2017:3047
https://access.redhat.com/errata/RHSA-2017:3046
https://access.redhat.com/errata/RHSA-2017:2999
https://access.redhat.com/errata/RHSA-2017:1222
https://access.redhat.com/errata/RHSA-2017:1221
https://access.redhat.com/errata/RHSA-2017:1220
http://www.oracle.com/technetwork/security-advisory/cpuoct2018-4428296.html
http://www.oracle.com/technetwork/security-advisory/cpuoct2017-3236626.html