XSS in Wwbn Avideo

CVE-2026-43878

WWBN AVideo is an open source video platform. In versions up to and including 29.0, plugin/Meet/iframe.php echoes the attacker-controlled user and pass query parameters unescaped into a JavaScript double-quoted string literal inside a <script> block. An attacker who sends a victim to a crafted URL can break out of the string and execute arbitrary JavaScript in the victim's browser in the context of the AVideo origin. No authentication is required if a public Meet schedule exists on the target. Commit 3298ced2bcf92e4f3acff6ce9bde14edf42ecb5b contains an updated fix.

Vulnerability class: XSS (Cross-Site Scripting)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.003 (20.8th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 21st percentile — 20.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-43878: held from 0.002 to 0.003.

EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-43878?
CVE-2026-43878 is a medium-severity vulnerability in Wwbn Avideo, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-05-11.
How severe is CVE-2026-43878?
Medium severity. CVSS v3 base score is 6.1 out of 10.