CVE-2026-43878 Video: Reflected XSS in plugin/Meet/iframe.php via Unescaped user and pass Parameters in JavaScript String Literal
Reflected XSS in AVideo allows attackers to execute arbitrary JavaScript in victims' browsers via crafted URLs, requiring no authentication if a public Meet schedule exists.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-43878?
CVE-2026-43878 is a medium-severity cross-site scripting vulnerability in WWBN AVideo, published on 11 May 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
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.
Weakness: CWE-79
Which versions are affected by CVE-2026-43878?
2 open source packages ship an affected version, including wwbn/avideo.
| Package | Affected | Fixed in |
|---|---|---|
wwbn/avideo Packagist | All versions to 29.0 | None |
wwbn/avideo Packagist | All versions to 29.0 | None |
How do I fix CVE-2026-43878?
No fix has been published for CVE-2026-43878 yet. Limit exposure of the affected software until one is available.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2026-43878 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-43878 exists.
Sources
Also known as GHSA-mm5f-8q57-4fc4.