CVE-2021-30539: 
vulnerability analysis and mitigation

CVE-2021-30539 is a security vulnerability identified in Google Chrome versions prior to 91.0.4472.77. The vulnerability stems from insufficient policy enforcement in content security policy that could allow a remote attacker to bypass content security policy via a crafted HTML page (NVD, Chrome Releases).

The vulnerability has been assigned a CVSS v3.1 Base Score of 5.4 (Medium) with the vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N. The CVSS v2.0 Base Score is 5.8 (Medium) with the vector (AV:N/AC:M/Au:N/C:P/I:P/A:N). The vulnerability is classified under CWE-863 (Incorrect Authorization) (NVD).

The vulnerability could allow remote attackers to bypass content security policy protections, potentially leading to unauthorized access to sensitive information or execution of malicious code within the context of the affected browser (Gentoo Security).

The vulnerability has been patched in Google Chrome version 91.0.4472.77 and later. Users and administrators are advised to upgrade to the latest version of Chrome to mitigate this security risk. Various Linux distributions have also released security updates addressing this vulnerability (Chrome Releases, Fedora Update).