Tittle:
WordPress Plugin SEO ALert <= 1.59 - Admin+ Stored XSS


References:
CVE-2023-2225

Author:
Taurus Omar 

Description:
The plugin does not sanitise and escape some of its settings, which could allow high privilege users such as admin to perform Stored Cross-Site Scripting attacks even when the unfiltered_html capability is disallowed (for example in multisite setup).

Affects Plugins:
SEO ALert - No known fix - plugin closed

Proof of Concept:

1. Go to Vanilla Beans » SEO Alert.
 
2. In "Slack Alert for" » "Slack Channel" add payload: "><audio src=x onerror=confirm("XSS")>
 
3. Save to get the XSS trigger. 

Classification:
Type XSS 
OWASP top 10 A7: Cross-Site Scripting (XSS)
CWE-79

wpScan:
https://wpscan.com/vulnerability/0af475ba-5c02-4f62-876d-6235a745bbd6