CVE-2026-41508 — OWASP Coraza WAF: Truncated multipart body bypasses MULTIPART_STRICT_ERROR (rule 200003) via silent io.ErrUnexpectedEOF handling
OWASP Coraza WAF is a golang modsecurity compatible web application firewall library. From 3.4.0 until 3.8.0, the multipart processor in internal/bodyprocessors/multipart.go tre…
Published: 2026-10-12 · CVSS: 5.8 · CVSS 3.1
OWASP Coraza WAF is a golang modsecurity compatible web application firewall library. From 3.4.0 until 3.8.0, the multipart processor in internal/bodyprocessors/multipart.go treats io.ErrUnexpectedEOF as nonfatal without setting MULTIPART_STRICT_ERROR. A remote attacker can submit a truncated multipart body that produces io.ErrUnexpectedEOF, causing parsing to stop without raising the strict-error signal used by the recommended defensive rule. Rules 200002 and 200003 do not fire, allowing multipart parser-disagreement payloads to reach a backend that interprets the truncated body differently. This issue is fixed in version 3.8.0.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7