In PHP versions 8.2.* before 8.2.31, 8.3.* before 8.3.31, 8.4.* before 8.4.21, and 8.5.* before 8.5.6, when a SOAP server has a typemap configured, the decoding process contains a mistake which checks the wrong variable in case of missing value element.  This leads to dereferences a NULL pointer, causing a segmentation fault. This allows a remote unauthenticated attacker to crash the PHP SOAP server process, resulting in denial of service.