An issue was discovered in PHP 7.x before 7.1.26, 7.2.x before 7.2.14, and 7.3.x before 7.3.2. dns_get_record misparses a DNS response, which can allow a hostile DNS server to cause PHP to misuse memcpy, leading to read operations going past the buffer allocated for DNS data. This affects php_parserr in ext/standard/dns.c for DNS_CAA and DNS_ANY queries.
The zend_string_extend function in Zend/zend_string.h in PHP through 7.1.5 does not prevent changes to string objects that result in a negative length, which allows remote attackers to cause a denial of service (application crash) or possibly have unspecified other impact by leveraging a script's use of .= with a long string.
Buffer overflow in the radius_get_vendor_attr function in the Radius extension before 1.2.7 for PHP allows remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via a large Vendor Specific Attributes (VSA) length value.
The parse_str function in (1) PHP, (2) Hardened-PHP, and (3) Suhosin, when called without a second parameter, might allow remote attackers to overwrite arbitrary variables by specifying variable names and values in the string to be parsed. NOTE: it is not clear whether this is a design limitation of the function or a bug in PHP, although it is likely to be regarded as a bug in Hardened-PHP and Suhosin.