Vulnerability Description
WWBN AVideo is an open source video platform. In versions up to and including 29.0, objects/notifySubscribers.json.php takes the raw message POST parameter and passes it into sendSiteEmail(), which substitutes it directly into an HTML email template (via str_replace on the {message} placeholder) and renders it with PHPMailer::msgHTML(). There is no HTML sanitization, character escaping, or output encoding on the attacker-controlled message between $_POST['message'] and the rendered email. Any authenticated user with upload permission can therefore broadcast arbitrary HTML — phishing links, tracking pixels, CSS/UI spoofing — to every subscriber on their channel (up to 10,000 recipients per invocation). The email is sent From: the platform's configured contact address and wrapped in the site's official logo and title, so attacker-supplied HTML arrives with the appearance of an official platform communication. Commit https://github.com/WWBN/AVideo/commit/ contains an updated fix.
CVSS Score
MEDIUM
Related Weaknesses (CWE)
References
- https://github.com/WWBN/AVideo/commit/078c4342eb9969a70425a9cdca3eefa7f8a86d53
- https://github.com/WWBN/AVideo/security/advisories/GHSA-g9cm-rxp7-6gv5
- https://github.com/WWBN/AVideo/security/advisories/GHSA-g9cm-rxp7-6gv5
FAQ
What is CVE-2026-43876?
CVE-2026-43876 is a vulnerability with a CVSS score of 6.4 (MEDIUM). WWBN AVideo is an open source video platform. In versions up to and including 29.0, objects/notifySubscribers.json.php takes the raw message POST parameter and passes it into sendSiteEmail(), which su...
How severe is CVE-2026-43876?
CVE-2026-43876 has been rated MEDIUM with a CVSS base score of 6.4/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-43876?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.