CVE 2014-4049
Heap-based buffer overflow in the php_parserr function in ext/standard/dns.c in PHP 5.6.0beta4 and earlier allows remote servers to cause a denial of service (crash) and possibly execute arbitrary code via a crafted DNS TXT record, related to the dns_get_record function.
See the 
CVE page on Mitre.org
for more details.
