Provide references for CVE-2019-20921.
Where can I find more information about CVE-2019-20921?
References are available at: https://www.npmjs.com/advisories/1522, https://snyk.io/vuln/SNYK-JS-BOOTSTRAPSELECT-570457, https://github.com/advisories/GHSA-9r7h-6639-v5mw, https://github.com/snapappointments/bootstrap-select/issues/2199.