Video: Reflected XSS in plugin/Meet/iframe.php via Unescaped user and pass Parameters in JavaScript String Literal

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

6.1 · CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

EPSS

• CVE-2026-43878: 0.25% estimated exploitation activity in the next 30 days; percentile 16.85 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary 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. Details Root cause is a two-step reflection with no escaping applied at the HTML/JS sink. Step 1 — User::loginFromRequestToGet() at objects/user.php:3363-3373 returns the raw concatenation of $REQUEST['user'] and $REQUEST['pass'] with no URL-encoding, HTML-escaping, or other sanitization: Step 2 — plugin/Meet/iframe.php builds $readyToClose from that string and emits it into a JS string literal without escaping: Note that xssesc() IS applied a few lines earlier to the adjacent nameIdentification parameter (line 45) — the developer knew about XSS here but missed…

Published by the source

5 May 2026, 19:15 UTC

Last modified by the source

13 May 2026, 14:19 UTC

Source last checked

26 Oct 2026, 14:40 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-mm5f-8q57-4fc4

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# Patch Next advisory brief: CVE-2026-43878

Advisory: Video: Reflected XSS in plugin/Meet/iframe.php via Unescaped user and pass Parameters in JavaScript String Literal
IDs: CVE-2026-43878, GHSA-mm5f-8q57-4fc4
Record: https://patchnext.com/advisories/cve-2026-43878 (revision 1, source checked 26 Oct 2026, 14:40 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 6.1)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor response not established. A vendor fix does not mean a deployment is fixed.

## Affected components
- Packagist wwbn/avideo: affected <= 29.0

## Suggested inspection (read-only)
- Packagist wwbn/avideo: check the installed version with your package manager.

## Supported action
No complete vendor fix is recorded. Follow the primary source's mitigation guidance and check this record again before closing anything.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on wwbn/avideo.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-mm5f-8q57-4fc4 (GitHub-reviewed advisory GHSA-mm5f-8q57-4fc4 lists affected ranges: Packagist wwbn/avideo >=0 <=29.0)

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