WordPress SEO Alert plugin versions 1.59 and below suffer from a persistent cross site scripting vulnerability.
advisories | CVE-2023-2225
WordPress Plugin SEO ALert <= 1.59 - Admin+ Stored XSS
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).
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.
OWASP top 10 A7: Cross-Site Scripting (XSS)