Amazon Linux AMI Security Advisory: ALAS-2015-488
Advisory Release Date: 2015-03-04 15:53 Pacific
Advisory Updated Date: 2015-03-04 16:12 Pacific
Format string vulnerability in the yyerror function in lib/cgraph/scan.l in Graphviz allows remote attackers to have unspecified impact via format string specifiers in unknown vector, which are not properly handled in an error string.
Run yum update graphviz-php to update your system.