Amazon Linux AMI Security Advisory: ALAS-2015-582
Advisory Release Date: 2015-08-17 12:31 Pacific
It was found that mailman did not sanitize the list name before passing it to certain MTAs. A local attacker could use this flaw to execute arbitrary code as the user running mailman. (CVE-2015-2775 )
It was found that mailman stored private email messages in a world-readable directory. A local user could use this flaw to read private mailing list archives. (CVE-2002-0389 )
Run yum update mailman to update your system.