{"id":"CVE-2026-71555","title":"PILOS (Platform for Interactive Live-Online Seminars) is a frontend for BigBlueButton","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 browsi…","severity":"medium","cvss":4.1,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:N/I:L/A:N","cwe":["CWE-1022"],"published":"2026-08-06","updated":"2026-09-10","sourceUpdated":"2026-09-10T20:42:39.707","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-71555","references":[{"url":"https://github.com/THM-Health/PILOS/commit/b50f2bd07c4f4a7d6a9981578238ae3579275d81","label":"security-advisories@github.com"},{"url":"https://github.com/THM-Health/PILOS/releases/tag/v4.14.1","label":"security-advisories@github.com"},{"url":"https://github.com/THM-Health/PILOS/security/advisories/GHSA-j4wr-p8gh-xrw5","label":"security-advisories@github.com"}],"tags":["nvd"],"epss":0.00293,"epssPercentile":0.19395,"ingestedAt":"2026-09-10T21:05:53.595Z","slug":"CVE-2026-71555","body":"## Overview\n\nPILOS (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.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":23,"depthScoreParts":{"impact":22.5,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}