The vulnerability was used to upload arbitrary files on the target system.
Vulnerability details
Advisory: SB2021060211 - Arbitrary file upload in Fancy Product Designer plugin for WordPress
Vulnerable component: Fancy Product Designer
CVE-ID: CVE-2021-24370
CVSSv3 score: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:H/RL:O/RC:C
CWE-ID: CWE-434 - Unrestricted Upload of File with Dangerous Type
Description:
The vulnerability allows a remote attacker to compromise vulnerable system.
The vulnerability exists due to insufficient validation of file during file upload in "wp-admin" or "wp-content/plugins/fancy-product-designer/inc". A remote attacker can upload a malicious file and execute it on the server.
Note, the vulnerability is being actively exploited in the wild.
External links:
https://www.wordfence.com/blog/2021/06/critical-0-day-in-fancy-product-designer-under-active-attack/