CVE-2026-71555
PILOS: Reverse tabnabbing in room 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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- Required
What an attacker can affect
- Confidentiality
- None
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
PILOS: Reverse tabnabbing in room 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.
- Record
CVE-2026-71555- CVSS 3.1
- 4.1 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:N/I:L/A:N - Weakness
- CWE-1022
- Updated
- 2026-11-02
EUVDEUVD-2026-54178
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.
- Record
EUVD-2026-54178- CVSS 3.1
- 4.1 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:N/I:L/A:N - Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-71555- CVSS 3.1
- 4.1 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:N/I:L/A:N - Weakness
- CWE-1022
- Updated
- 2026-11-02
OSV
PILOS: Reverse tabnabbing in room 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.
- Record
CVE-2026-71555- CVSS 3.1
- 4.1 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:N/I:L/A:N - Weakness
- CWE-1022
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-71555 is a medium vulnerability (CVSS 4.1) in Thm-health Pilos, published August 6, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.29%, the 21st percentile. No source names a fixed version.
References
github.com/THM-Health/PILOS/security/advisories/GHSA-j4wr-p8gh-xrw5
nvd.nist.gov/vuln/detail/CVE-2026-71555