CVE-2026-8420: BLOGCHAT Chat System <= 1.3.6.3 - Cross-Site Request Forgery to Stored Cross-Site Scripting via Settings Update

Severity: medium (CVSS 6.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-05-20 · updated 2026-07-23
Weakness: CWE-352

Description

The BLOGCHAT Chat System plugin for WordPress is vulnerable to Cross-Site Request Forgery in all versions up to, and including, 1.3.6.3. This is due to missing or incorrect nonce validation on a function. This makes it possible for unauthenticated attackers to update settings and inject malicious web scripts via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.

Affected products

rdbeach BLOGCHAT Chat System: through 1.3.6.3

References

https://plugins.trac.wordpress.org/browser/blogchat-chat-system/tags/1.3.6.3/wp-blogchat-widget.php#L208
https://plugins.trac.wordpress.org/browser/blogchat-chat-system/tags/1.3.6.3/wp-blogchat-widget.php#L215
https://plugins.trac.wordpress.org/browser/blogchat-chat-system/tags/1.3.6.3/wp-blogchat-widget.php#L222
https://plugins.trac.wordpress.org/browser/blogchat-chat-system/tags/1.3.6.3/wp-blogchat-widget.php#L293
https://plugins.trac.wordpress.org/browser/blogchat-chat-system/trunk/wp-blogchat-widget.php#L208
https://plugins.trac.wordpress.org/browser/blogchat-chat-system/trunk/wp-blogchat-widget.php#L215
https://plugins.trac.wordpress.org/browser/blogchat-chat-system/trunk/wp-blogchat-widget.php#L222
https://plugins.trac.wordpress.org/browser/blogchat-chat-system/trunk/wp-blogchat-widget.php#L293
https://www.wordfence.com/threat-intel/vulnerabilities/id/a62186aa-19aa-445b-8fdc-b029bdafd58f?source=cve

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