GHSA-445c-vh5m-36rj Apache Log4j Core: log injection in `Rfc5424Layout` due to silent configuration incompatibility

• Maven org.apache.logging.log4j:log4j-core: >= 2.21.0, < 2.25.4 → fixed in 2.25.4 • Maven org.apache.logging.log4j:log4j-core: >= 3.0.0-beta1, <= 3.0.0-beta3 (no fix yet)

Apache Log4j Core's `Rfc5424Layout`, 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 users of stream-based syslog services who configure Rfc5424Layout directly: • The `newLineEscape` attribute was silently renamed, causing newline escaping to stop working for users of TCP framing (RFC 6587), exposing them to CRLF injection in log output. • The `useTlsMessageFormat` attribute was silently renamed, causing users of TLS framing (RFC 5425) to be silently downgraded to unframed TCP (RFC 6587), without newline escaping. Users of the `SyslogAppender` are not affected, as its configuration attributes were not modified. Users are advised to upgrade to Apache Log4j Core 2.25.4, which corrects this issue.