VULNERABILITY INTELLIGENCE

CVE-2026-43876

CVSS score6.4 MEDIUM
EPSS probability0.19%
CISA KEVNot currently listed
Published2026-05-11
Last modified2026-10-26
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N

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.

Weakness classification

  • security-advisories@github.com: CWE-79

Primary references