GraphicsMagick 1.3.26 has a NULL pointer dereference in the WriteMAPImage() function in coders/map.c when processing a non-colormapped image, a different vulnerability than CVE-2017-11638.
http://hg.code.sf.net/p/graphicsmagick/code/rev/29550606d8b9
http://www.securityfocus.com/bid/100395
https://lists.debian.org/debian-lts-announce/2018/08/msg00002.html
Source: MITRE
Published: 2017-07-26
Updated: 2018-10-18
Type: CWE-476
Base Score: 6.8
Vector: AV:N/AC:M/Au:N/C:P/I:P/A:P
Impact Score: 6.4
Exploitability Score: 8.6
Severity: MEDIUM
Base Score: 8.8
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Impact Score: 5.9
Exploitability Score: 2.8
Severity: HIGH