Apache Log4j Core: Silent log event loss in XmlLayout due to unescaped XML 1.0 forbidden characters

CVE-2026-34480 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 l...

Security Bulletin: IBM Watson Discovery for IBM Cloud Pak for Data affected by vulnerability in log4j-core

Summary IBM Watson Discovery for IBM Cloud Pak for Data affected by vulnerability in log4j-core Vulnerability Details CVEID:CVE-2026-34480 DESCRIPTION: 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 t...

CVE-2026-40021

Apache Log4net before version 3.3.0 contains a vulnerability in XmlLayout and XmlLayoutSchemaLog4J where characters forbidden by XML 1.0 are not sanitized in MDC keys/values and the identity field. The issue causes a serialization exception and silent loss of the affected log event, which can be ...