Amazon Linux: Security Advisory (ALAS-2015-572)

The remote host is missing an update announced via the referenced Security Advisory.

It was found that libuser, as used in the chfn userhelper functionality, does not properly filter out newline characters, which allows an authenticated local attacker to corrupt the /etc/passwd file and cause denial-of-service against the system. (CVE-2015-3245 )A flaw was found in the way the libuser library handled the /etc/passwd file. A local attacker could use an application compiled against libuser (for example, userhelper) to manipulate the /etc/passwd file, which could result in a denial of service or possibly allow the attacker to escalate their privileges to root. (CVE-2015-3246 )

Run yum update usermode libuser to update your system.