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CVE-2026-71555 (GCVE-0-2026-71555)

Vulnerability from cvelistv5 – Published: 2026-08-06 21:51 – Updated: 2026-08-07 17:26
VLAI
Title
PILOS: Reverse tabnabbing in room description
Summary
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.
Severity
4.1 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:N/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-07 17:25 UTC
CWE
  • CWE-1022 - Use of Web Link to Untrusted Target with window.opener Access
Assigner
References
Impacted products
Vendor Product Version CPE status
THM-Health PILOS Affected: >= 2.1.0, < 4.14.1
guessed Create a notification for this product.
Show details on NVD website
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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
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