vBulletin through 5.5.4 mishandles custom avatars.
https://forum.vbulletin.com/forum/vbulletin-announcements/vbulletin-announcements_aa/4423646-vbulletin-5-5-x-5-5-2-5-5-3-and-5-5-4-security-patch-level-2
http://seclists.org/fulldisclosure/2019/Oct/9
http://packetstormsecurity.com/files/154759/vBulletin-5.5.4-Remote-Code-Execution.html
Source: Mitre, NVD
Published: 2019-10-04
Updated: 2021-07-21
Base Score: 6.8
Vector: CVSS2#AV:N/AC:M/Au:N/C:P/I:P/A:P
Severity: Medium
Base Score: 9.8
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Severity: Critical