National Cyber Awareness System:
The Linux GNU C Library (glibc) versions prior to 2.18 are vulnerable to remote code execution via a vulnerability in the gethostbyname function. Exploitation of this vulnerability may allow a remote attacker to take control of an affected system. Linux distributions employing glibc-2.18 and later are not affected.
US-CERT recommends users and administrators refer to their respective Linux or Unix-based OS vendor(s) for an appropriate patch if affected. Patches are available from Ubuntu and Red Hat. The GNU C Library versions 2.18 and later are also available for experienced users and administrators to implement.