The wp-slimstat (aka Slimstat Analytics) plugin before 4.1.6.1 for WordPress has XSS via an HTTP Referer header, or via a field associated with JavaScript-based Referer tracking.
https://www.openwall.com/lists/oss-security/2015/07/30/1
https://plugins.trac.wordpress.org/changeset/1204104
http://plugins.svn.wordpress.org//wp-slimstat/tags/4.1.6.1/readme.txt
Source: Mitre, NVD
Published: 2018-10-07
Updated: 2018-11-19
Base Score: 4.3
Vector: CVSS2#AV:N/AC:M/Au:N/C:N/I:P/A:N
Severity: Medium
Base Score: 6.1
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
EPSS: 0.00265