Name: CVE-2021-23955: Improper Restriction of Rendered UI Layers or Frames
Creator: Rapid7
Published: 2021-02-26T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2021-23955, CWE-1021, CVSS 6.1, EPSS 0.00238

The browser could have been confused into transferring a pointer lock state into another tab, which could have lead to clickjacking attacks. This vulnerability affects Firefox < 85.

CVSS Details

CVSS 3.1 Base Score: 6.1
CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Alpine Linux	—	Upgrade firefoxUpgrade librewolf	Aug 22, 2024	Feb 26, 2021
Arch Linux	—	Upgrade to the latest version of Arch Linux	Jul 11, 2025	Feb 26, 2021
Gentoo Linux	—	Upgrade www-client/firefox.Upgrade www-client/firefox-bin.	Feb 1, 2021	Feb 1, 2021
Mfsa2021 03	—	Upgrade to Mozilla Firefox version 85.0Upgrade to the latest version of Mozilla Firefox	Jan 27, 2021	Jan 26, 2021
Ubuntu	—	Upgrade firefox	Feb 2, 2021	Feb 1, 2021

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CVSS Details

Covered by Rapid7

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