CVE-2026-15603

A flaw was found in morgan, an HTTP request logger middleware for Node.js. An unauthenticated remote client can inject specific Unicode line separator characters into log token values. This manipulation can cause downstream log processing systems to misinterpret a single log entry as multiple records, leading to log forging. Log forging allows an attacker to inject false entries into log files, potentially obscuring malicious activities or hindering incident response.

Log forging flaw in morgan allows unauthenticated remote attackers to inject Unicode line separators into log tokens. This can lead to log record misinterpretation by downstream systems, potentially impacting security monitoring and incident response in Red Hat products that use morgan as an HTTP request logger middleware.

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.