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CVE-2026-34478

Estado: AnalizadaMedia (6.9)—

Apache Log4j Core's Rfc5424Layout https://logging.apache.org/log4j/2.x/manual/layouts.html#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:

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.

Detalles técnicos trazas, registros y código del informe original
  *  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.

CVSS

Probabilidad de explotación (EPSS)

EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).

Tecnologías afectadas (1)

Apache — Log4j

CWE

Referencias

JSON original (NVD)

Mostrar
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    }
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  "lastModified": "2026-06-17T10:39:06.800",
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