CVE-2026-34481 Apache Log4j JSON Template Layout: Improper serialization of non-finite floating-point values in JsonTemplateLayout

Apache Log4j's JsonTemplateLayout https://logging.apache.org/log4j/2.x/manual/json-template-layout.html , in versions up to and including 2.25.3, produces invalid JSON output when log events contain non-finite floating-point values NaN, Infinity, or -Infinity, which are prohibited by RFC 8259. Th...

CVE-2026-34481 Apache Log4j JSON Template Layout: Improper serialization of non-finite floating-point values in JsonTemplateLayout

Apache Log4j's JsonTemplateLayout https://logging.apache.org/log4j/2.x/manual/json-template-layout.html , in versions up to and including 2.25.3, produces invalid JSON output when log events contain non-finite floating-point values NaN, Infinity, or -Infinity, which are prohibited by RFC 8259. Th...

CVE-2026-34481 Apache Log4j JSON Template Layout: Improper serialization of non-finite floating-point values in JsonTemplateLayout

Apache Log4j's JsonTemplateLayout https://logging.apache.org/log4j/2.x/manual/json-template-layout.html , in versions up to and including 2.25.3, produces invalid JSON output when log events contain non-finite floating-point values NaN, Infinity, or -Infinity, which are prohibited by RFC 8259. Th...

CVE-2026-34480 Apache Log4j Core: Silent log event loss in XmlLayout due to unescaped XML 1.0 forbidden characters

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-2026-34480 Apache Log4j Core: Silent log event loss in XmlLayout due to unescaped XML 1.0 forbidden characters

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-2026-34480 Apache Log4j Core: Silent log event loss in XmlLayout due to unescaped XML 1.0 forbidden characters

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-2026-34480

Technical details about CVE-2026-34480 are not publicly available in the provided connected documents. The initial description gives an overview but no vendor/product/version specifics or remediation steps here. Monitor for updates from official advisories.

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 log message or M...

CVE-2026-34478 Apache Log4j Core: Log injection in Rfc5424Layout due to silent configuration incompatibility

Apache Log4j Core's Rfc5424Layout https://logging.apache.org/log4j/2.x/manual/layouts.htmlRFC5424Layout , in versions 2.21.0 through 2.25.3, is vulnerable to log injection via CRLF sequences due to undocumented renames of security-relevant configuration attributes. Two distinct issues affect user...

CVE-2026-34478

Apache Log4j Core's Rfc5424Layout https://logging.apache.org/log4j/2.x/manual/layouts.htmlRFC5424Layout , in versions 2.21.0 through 2.25.3, is vulnerable to log injection via CRLF sequences due to undocumented renames of security-relevant configuration attributes. Two distinct issues affect user...

CVE-2026-34478 Apache Log4j Core: Log injection in Rfc5424Layout due to silent configuration incompatibility

Apache Log4j Core's Rfc5424Layout https://logging.apache.org/log4j/2.x/manual/layouts.htmlRFC5424Layout , in versions 2.21.0 through 2.25.3, is vulnerable to log injection via CRLF sequences due to undocumented renames of security-relevant configuration attributes. Two distinct issues affect user...

CVE-2026-34478

CVE-2026-34478 (Log4j Core) affects Apache Log4j Core 2.21.0 through 2.25.3 and involves CRLF log-injection risks in stream-based syslog output due to undocumented renames of configuration attributes in Rfc5424Layout. Specifically, the newLineEscape attribute was silently renamed, breaking newlin...

CVE-2026-34477 Apache Log4j Core: verifyHostName attribute silently ignored in TLS configuration, allowing hostname verification bypass

The fix for CVE-2025-68161 https://logging.apache.org/security.htmlCVE-2025-68161 was incomplete: it addressed hostname verification only when enabled via the log4j2.sslVerifyHostName https://logging.apache.org/log4j/2.x/manual/systemproperties.htmllog4j2.sslVerifyHostName system property, but no...

CVE-2026-34477

CVE-2025-68161 (and CVE-2026-34477) affect Apache Log4j Core Socket Appender where TLS hostname verification was silently ignored when configured via verifyHostName, leaving potential MITM scenarios under SMTP, Socket, or Syslog Appenders using a nested element. The issue spans versions 2.0-beta...

CVE-2026-34477 Apache Log4j Core: verifyHostName attribute silently ignored in TLS configuration, allowing hostname verification bypass

The fix for CVE-2025-68161 https://logging.apache.org/security.htmlCVE-2025-68161 was incomplete: it addressed hostname verification only when enabled via the log4j2.sslVerifyHostName https://logging.apache.org/log4j/2.x/manual/systemproperties.htmllog4j2.sslVerifyHostName system property, but no...

CVE-2026-34477

The fix for CVE-2025-68161 https://logging.apache.org/security.htmlCVE-2025-68161 was incomplete: it addressed hostname verification only when enabled via the log4j2.sslVerifyHostName https://logging.apache.org/log4j/2.x/manual/systemproperties.htmllog4j2.sslVerifyHostName system property, but no...

CVE-2026-34477 Apache Log4j Core: verifyHostName attribute silently ignored in TLS configuration, allowing hostname verification bypass

The fix for CVE-2025-68161 https://logging.apache.org/security.htmlCVE-2025-68161 was incomplete: it addressed hostname verification only when enabled via the log4j2.sslVerifyHostName https://logging.apache.org/log4j/2.x/manual/systemproperties.htmllog4j2.sslVerifyHostName system property, but no...

Exploit for Uncontrolled Resource Consumption in Siemens 6Bk1602-0Aa12-0Tp0_Firmware

CVE-2021-44228 — Log4Shell PoC Lab DISCLAIMER Este...

Apache Log4j 安全漏洞

Apache Log4j is an open-source logging tool based on Java, developed by the Apache Foundation in the United States. Versions of Apache Log4j JSON Template Layout 2.25.3 and earlier contain security vulnerabilities. These vulnerabilities arise from the JsonTemplateLayout generating invalid JSON...

Apache Log4j 安全漏洞

Apache Log4j is an open-source logging tool based on Java, developed by the Apache Foundation in the United States. Versions of Apache Log4j Core 2.25.3 and earlier contain security vulnerabilities. These vulnerabilities stem from the silent ignoring of the verifyHostName configuration property,...