SlimStat Analytics < 5.5.0 - Unauthenticated Stored XSS via CF-IPCountry Header

The SlimStat Analytics WordPress plugin before 5.5.0 does not escape a visitor-controlled geolocation value before outputting it in its admin analytics reports, allowing unauthenticated visitors to store a cross-site scripting payload that executes in the browser of an administrator who views the reports. Exploitation requires the SlimStat Analytics WordPress plugin before 5.5.0 to be configured to use the Cloudflare geolocation provider.