CVE-2026-71555

Medium

Description

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.

SeverityMedium
CVSS4.1
Exploit probability—
ProductPILOS
PublishedAug 6, 2026
First seenAug 6, 2026
Weakness typeCWE-1022CWE-1022

How to fix

Sources list no fixed version or patch link for this vulnerability.

Affected products

ProductAffected versionsFixed in
THM-Health PILOS>= 2.1.0, < 4.14.1—

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CVE-2026-71555 · PILOS · Dark Radar