CVE-2026-40021 Apache Log4net: Silent log event loss in XmlLayout and XmlLayoutSchemaLog4J due to unescaped XML 1.0 forbidden characters

Apache Log4net's XmlLayout https://logging.apache.org/log4net/manual/configuration/layouts.htmllayout-list and XmlLayoutSchemaLog4J https://logging.apache.org/log4net/manual/configuration/layouts.htmllayout-list , in versions before 3.3.0, fail to sanitize characters forbidden by the XML 1.0...

Apache Log4cxx 安全漏洞

Apache Log4cxx is a C++ logging framework developed by the Apache Foundation, based on the Apache log4j framework. Versions of Apache Log4cxx prior to 1.7.0 contained security vulnerabilities. These vulnerabilities stemmed from XMLLayout not clearing characters prohibited by the XML 1.0...

PT-2026-31983

Name of the Vulnerable Software and Affected Versions Apache Log4cxx versions prior to 1.7.0 Description Apache Log4cxx's XMLLayout fails to sanitize characters forbidden by the XML 1.0 specification in log messages, NDC, and MDC property keys and values, resulting in invalid XML output. This can...

CVE-2026-40021: Improper Encoding or Escaping of Output

Apache Log4net's XmlLayout https://logging.apache.org/log4net/manual/configuration/layouts.htmllayout-list and XmlLayoutSchemaLog4J https://logging.apache.org/log4net/manual/configuration/layouts.htmllayout-list , in versions before 3.3.0, fail to sanitize characters forbidden by the XML 1.0...

CVE-2026-34480: Improper Encoding or Escaping of Output

Apache Log4j Core's XmlLayout https://logging.apache.org/log4j/2.x/manual/layouts.htmlXmlLayout , in versions up to and including 2.25.3, fails to sanitize characters forbidden by the XML 1.0 specification https://www.w3.org/TR/xml/charsets producing invalid XML output whenever a log message or M...

CVE-2026-40023: Improper Encoding or Escaping of Output

Apache Log4cxx's XMLLayout https://logging.apache.org/log4cxx/1.7.0/classlog4cxx11xml11XMLLayout.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, producin...

PT-2026-31942

Name of the Vulnerable Software and Affected Versions Apache Log4j Core versions up to and including 2.25.3 Description Apache Log4j Core's XmlLayout fails to sanitize characters forbidden by the XML 1.0 specification, resulting in invalid XML output when log messages or MDC values contain such...