{"id":"CVE-2026-66046","state":"PUBLISHED","title":"Expat Denial of Service via storeAtts() Quadratic Complexity","description":"Expat through 2.8.3 contains a denial of service vulnerability caused by quadratic algorithmic complexity in the storeAtts() function in xmlparse.c, where processing N specified attributes with non-normalized values triggers an O(N^2) linear scan of elementType->defaultAtts to determine CDATA status. 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