CVE-2026-41504: OWASP Coraza WAF: Native audit-log format allows CRLF injection and log forgery via request body and header fields

Vulnerability summary

CVE-2026-41504 is a medium (CVSS 5.8) vulnerability in corazawaf coraza. EPSS estimates a 0.36% chance of exploitation in the next 30 days, higher than 29.2% of scored vulnerabilities.

Timeline

1. 12-10-2026
   PublishedVulnerability first disclosed.
2. 13-10-2026
   Last modifiedVulnerability information updated.

Description

OWASP Coraza WAF is a golang modsecurity compatible web application firewall library. From 3.0.0 until 3.8.0, the Native audit-log formatter in internal/auditlog/formats.go writes attacker-influenced request and response fields without neutralizing carriage returns or line feeds. When SecAuditLogFormat Native is enabled, injected line breaks can create forged lines inside a transaction record. An attacker who controls request or response body, header, error-message, or matched-rule data can inject carriage returns and line feeds that appear as forged audit lines within a transaction record. The forged content can mislead operators and line-oriented SIEM processing, although the unpredictable transaction boundary prevents straightforward impersonation of a separate complete session. This issue is fixed in version 3.8.0.

• CWE-93Improper Neutralization of CRLF SequencesThe product uses CRLF (carriage return line feeds) as a special element, e.g. to separate lines or records, but it does not neutralize or incorrectly neutralizes CRLF sequences from inputs.
• CWE-117Improper Output Neutralization for LogsThe product constructs a log message from external input, but it does not neutralize or incorrectly neutralizes special elements when the message is written to a log file.