Amazon Linux AMI Security Advisory: ALAS-2014-323
Advisory Release Date: 2014-04-10 23:55 Pacific
Advisory Updated Date: 2014-09-18 00:20 Pacific
The BEGIN regular expression in the awk script detector in magic/Magdir/commands in file before 5.15 uses multiple wildcards with unlimited repetitions, which allows context-dependent attackers to cause a denial of service (CPU consumption) via a crafted ASCII file that triggers a large amount of backtracking, as demonstrated via a file with many newline characters.
Run yum update file to update your system.