CVE-2026-34478

A flaw was found in Apache Log4j Core. This vulnerability allows for log injection through the use of Carriage Return Line Feed (CRLF) sequences. This occurs because security-related configuration attributes were silently renamed, impacting users who directly configure Rfc5424Layout with stream-based syslog services. An attacker could exploit this to inject malicious data into log files, potentially obscuring critical security events or manipulating system records.

This vulnerability allows log injection via CRLF sequences due to silently renamed security attributes in Rfc5424Layout. This affects Red Hat products that directly configure Rfc5424Layout with stream-based syslog services, potentially enabling an attacker to obscure or manipulate log records. This impact is limited to specific configurations, as users of the SyslogAppender are not affected.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.