gdImageClone in gd.c in libgd 2.1.0-rc2 through 2.2.5 has a NULL pointer dereference allowing attackers to crash an application via a specific function call sequence. Only affects PHP when linked with an external libgd (not bundled).
https://bugzilla.redhat.com/show_bug.cgi?id=1599032
https://github.com/libgd/libgd/pull/580
https://github.com/libgd/libgd/commit/a93eac0e843148dc2d631c3ba80af17e9c8c860f
https://lists.debian.org/debian-lts-announce/2020/02/msg00014.html
http://lists.opensuse.org/opensuse-security-announce/2020-03/msg00020.html
Source: MITRE
Published: 2020-02-11
Updated: 2021-12-30
Type: CWE-476
Base Score: 4.3
Vector: AV:N/AC:M/Au:N/C:N/I:N/A:P
Impact Score: 2.9
Exploitability Score: 8.6
Severity: MEDIUM
Base Score: 7.5
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Impact Score: 3.6
Exploitability Score: 3.9
Severity: HIGH