{"id":"CVE-2026-41508","state":"PUBLISHED","title":"OWASP Coraza WAF: Truncated multipart body bypasses MULTIPART_STRICT_ERROR (rule 200003) via silent io.ErrUnexpectedEOF handling","description":"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.","publishedAt":"2026-10-12T20:01:09.451Z","updatedAt":"2026-10-13T20:24:17.217Z","severity":{"score":5.8,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["corazawaf coraza"],"affected":[{"vendor":"corazawaf","product":"coraza","versions":[{"version":">= 3.4.0, < 3.8.0","status":"affected"}]}],"references":["https://github.com/corazawaf/coraza/security/advisories/GHSA-r3rm-qphw-hh76","https://github.com/corazawaf/coraza/commit/f94c81bec209f658120c418448d0590a549b71df","https://github.com/corazawaf/coraza/releases/tag/v3.8.0"],"weaknesses":["CWE-693","CWE-755"],"ingestedAt":"2026-10-29T20:11:57.932Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/41xxx/CVE-2026-41508.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-41508","state":"PUBLISHED","datePublished":"2026-10-12T20:01:09.451Z","dateUpdated":"2026-10-13T20:24:17.217Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-04-20T18:18:50.681Z"},"containers":{"cna":{"title":"OWASP Coraza WAF: Truncated multipart body bypasses MULTIPART_STRICT_ERROR (rule 200003) via silent io.ErrUnexpectedEOF handling","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"corazawaf","product":"coraza","versions":[{"version":">= 3.4.0, < 3.8.0","status":"affected"}]}],"references":[{"url":"https://github.com/corazawaf/coraza/security/advisories/GHSA-r3rm-qphw-hh76","name":"https://github.com/corazawaf/coraza/security/advisories/GHSA-r3rm-qphw-hh76","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/corazawaf/coraza/commit/f94c81bec209f658120c418448d0590a549b71df","name":"https://github.com/corazawaf/coraza/commit/f94c81bec209f658120c418448d0590a549b71df","tags":["x_refsource_MISC"]},{"url":"https://github.com/corazawaf/coraza/releases/tag/v3.8.0","name":"https://github.com/corazawaf/coraza/releases/tag/v3.8.0","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":5.8,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"LOW","privilegesRequired":"NONE","scope":"CHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-693","lang":"en","description":"CWE-693: Protection Mechanism Failure","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-755","lang":"en","description":"CWE-755: Improper Handling of Exceptional Conditions","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-10-12T20:01:09.451Z"},"source":{"advisory":"GHSA-r3rm-qphw-hh76","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-10-13T20:19:07.186164Z","id":"CVE-2026-41508","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-13T20:24:17.217Z"}}]}}}