GHSA-C7Q8-3CH8-VQPV xmldom: Processing Instruction Target Injection Bypasses requireWellFormed

Summary Document.createProcessingInstruction in @xmldom/xmldom performs no validation on the target parameter. The requireWellFormed: true serializer option validates only for : in the target and a case-insensitive xml prefix, but does not check for characters. A in the target breaks the processi...