CVE-2026-71555

PILOS (Platform for Interactive Live-Online Seminars) is a frontend for BigBlueButton. From 2.1.0 until 4.14.1, PILOS does not send a Cross-Origin-Opener-Policy response header, so pages opened by PILOS via a link that opens a new browsing context (e.g., target="_blank") retain a window.opener reference back to the originating PILOS tab. A malicious destination page reached this way can use window.opener to navigate or manipulate the original PILOS tab, a technique known as reverse tabnabbing, potentially redirecting an authenticated user to a phishing page that mimics PILOS. This issue is fixed in version 4.14.1.

CVSS v3 4.1 MEDIUM

4.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.3 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/THM-Health/PILOS/commit/b50f2bd07c4f4a7d6a9981578238ae3579275d81
https://github.com/THM-Health/PILOS/releases/tag/v4.14.1
https://github.com/THM-Health/PILOS/security/advisories/GHSA-j4wr-p8gh-xrw5

Configurations

No configuration.

History

23 Oct 2026, 21:10

Type	Values Removed	Values Added
Summary		(es) PILOS (Plataforma para Seminarios Interactivos en Vivo y en Línea) es un frontend para BigBlueButton. Desde la versión 2.1.0 hasta la 4.14.1, PILOS no envía una cabecera de respuesta Cross-Origin-Opener-Policy, por lo que las páginas abiertas por PILOS a través de un enlace que abre un nuevo contexto de navegación (por ejemplo, target=’_blank’) retienen una referencia window.opener de vuelta a la pestaña PILOS de origen. Una página de destino maliciosa alcanzada de esta manera puede usar window.opener para navegar o manipular la pestaña PILOS original, una técnica conocida como reverse tabnabbing, redirigiendo potencialmente a un usuario autenticado a una página de phishing que imita a PILOS. Este problema está solucionado en la versión 4.14.1.

Information

Published : 2026-08-06 22:18

Updated : 2026-10-24 15:10

NVD link : CVE-2026-71555

Mitre link : CVE-2026-71555

CVE.ORG link : CVE-2026-71555

JSON object : View

Products Affected

No product.

CWE

CWE-1022

Use of Web Link to Untrusted Target with window.opener Access

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