{"api_version":"1","generated_at":"2026-04-10T20:19:34+00:00","cve":"CVE-2026-40023","urls":{"html":"https://cve.report/CVE-2026-40023","api":"https://cve.report/api/cve/CVE-2026-40023.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-40023","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-40023"},"summary":{"title":"Apache Log4cxx, Apache Log4cxx (Conan), Apache Log4cxx (Brew): Silent log event loss in XMLLayout due to unescaped XML 1.0 forbidden characters","description":"Apache Log4cxx's  XMLLayout https://logging.apache.org/log4cxx/1.7.0/classlog4cxx_1_1xml_1_1XMLLayout.html , in versions before 1.7.0, fails to sanitize characters forbidden by the  XML 1.0 specification https://www.w3.org/TR/xml/#charsets  in log messages, NDC, and MDC property keys and values, producing invalid XML output. 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