numbers.c in libxslt before 1.1.43 has a use-after-free because, in nested XPath evaluations, an XPath context node can be modified but never restored

numbers.c in libxslt before 1.1.43 has a use-after-free because, in nested XPath evaluations, an XPath context node can be modified but never restored. This is related to xsltNumberFormatGetValue, xsltEvalXPathPredicate, xsltEvalXPathStringNs, and xsltComputeSortResultInternal.