PHP » PHP : Security Vulnerabilities Published In 2013 (Memory corruption)

The asn1_time_to_time_t function in ext/openssl/openssl.c in PHP before 5.3.28, 5.4.x before 5.4.23, and 5.5.x before 5.5.7 does not properly parse (1) notBefore and (2) notAfter timestamps in X.509 certificates, which allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption) via a crafted certificate that is not properly handled by the openssl_x509_parse function.

ext/xml/xml.c in PHP before 5.3.27 does not properly consider parsing depth, which allows remote attackers to cause a denial of service (heap memory corruption) or possibly have unspecified other impact via a crafted document that is processed by the xml_parse_into_struct function.