png_image_free in png.c in libpng 1.6.x before 1.6.37 has a use-after-free because png_image_free_function is called under png_safe_execute.
https://www.oracle.com/technetwork/security-advisory/cpujul2019-5072835.html
https://www.oracle.com/security-alerts/cpuoct2021.html
https://www.oracle.com/security-alerts/cpuApr2021.html
https://www.debian.org/security/2019/dsa-4451
https://www.debian.org/security/2019/dsa-4448
https://www.debian.org/security/2019/dsa-4435
https://usn.ubuntu.com/4083-1/
https://usn.ubuntu.com/4080-1/
https://usn.ubuntu.com/3997-1/
https://usn.ubuntu.com/3991-1/
https://usn.ubuntu.com/3962-1/
https://support.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbst03977en_us
https://security.netapp.com/advisory/ntap-20190719-0005/
https://security.gentoo.org/glsa/201908-02
https://seclists.org/bugtraq/2019/May/67
https://seclists.org/bugtraq/2019/May/59
https://seclists.org/bugtraq/2019/May/56
https://seclists.org/bugtraq/2019/Apr/36
https://seclists.org/bugtraq/2019/Apr/30
https://lists.debian.org/debian-lts-announce/2019/05/msg00038.html
https://lists.debian.org/debian-lts-announce/2019/05/msg00032.html
https://github.com/glennrp/libpng/issues/275
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=12803
https://access.redhat.com/errata/RHSA-2019:2737
https://access.redhat.com/errata/RHSA-2019:2592
https://access.redhat.com/errata/RHSA-2019:2590
https://access.redhat.com/errata/RHSA-2019:2585
https://access.redhat.com/errata/RHSA-2019:2495
https://access.redhat.com/errata/RHSA-2019:2494
https://access.redhat.com/errata/RHSA-2019:1310
https://access.redhat.com/errata/RHSA-2019:1309
https://access.redhat.com/errata/RHSA-2019:1308
https://access.redhat.com/errata/RHSA-2019:1269
https://access.redhat.com/errata/RHSA-2019:1267
https://access.redhat.com/errata/RHSA-2019:1265
http://www.securityfocus.com/bid/108098
http://packetstormsecurity.com/files/152561/Slackware-Security-Advisory-libpng-Updates.html
http://lists.opensuse.org/opensuse-security-announce/2019-08/msg00044.html
http://lists.opensuse.org/opensuse-security-announce/2019-08/msg00038.html
http://lists.opensuse.org/opensuse-security-announce/2019-06/msg00084.html
http://lists.opensuse.org/opensuse-security-announce/2019-06/msg00029.html
http://lists.opensuse.org/opensuse-security-announce/2019-06/msg00002.html