Provide references for CVE-2021-26539.
Where can I find more information about CVE-2021-26539?
References are available at: https://github.com/apostrophecms/sanitize-html/blob/main/CHANGELOG.md#231-2021-01-22, https://github.com/apostrophecms/sanitize-html/pull/458, https://advisory.checkmarx.net/advisory/CX-2021-4308.