Oracle Linux: CVE-2021-21702: ELSA-2021-4213: php:7.4 security, bug fix, and enhancement update (MODERATE)

In PHP versions 7.3.x below 7.3.27, 7.4.x below 7.4.15 and 8.0.x below 8.0.2, when using SOAP extension to connect to a SOAP server, a malicious SOAP server could return malformed XML data as a response that would cause PHP to access a null pointer and thus cause a crash.
A NULL pointer dereference issue is in the SOAP extension of PHP. More specifically, the flaw occurs in the SoapClient when parsing a WSDL document due to improper checking of a child node name. A malicious or compromised server replies with a crafted WSDL document, leading to a denial of service of the SoapClient accessing said document. The highest threat from this vulnerability is to system availability.