Update vulnerabilities.md

Author: mikesamuel

docs/vulnerabilities.md

@@ -1,4 +1,4 @@
 # Known & public vulnerabilities in this project
 
-  * [CVE-2021-42575](cve202142575.md) - 18 Oct. 2021 - Recommend upgrade to latest version.
+  * [CVE-2021-42575](cve202142575.md) - 18 Oct. 2021 - Recommend upgrade to v20211018.1 or later.
   * [CVE-2011-4457](cve20114457.md) - 17 Nov. 2011 - Recommend upgrade to r88 or later.