Ubuntu Security Notice 3239-2 – USN-3239-1 fixed vulnerabilities in the GNU C Library. Unfortunately, the fix for CVE-2015-5180 introduced an internal ABI change within the resolver library. This update reverts the change. Please note that long-running services that were restarted to compensate for the USN-3239-1 update may need to be restarted again. Various other issues were also addressed.