MediumFix available

Coraza: URL-encoded form Content-Type parameters bypass Coraza body inspection

Type: advisorySources: OSV2 source records

### Summary Coraza fails to inspect URL-encoded form bodies when their valid `Content-Type` contains a media-type parameter, for example: ```http Content-Type: application/x-www-form-urlencoded; charset=UTF-8 ``` An unauthenticated attacker can use this header to hide the complete form body from custom Coraza rules that inspect `ARGS_POST` or `REQUEST_BODY`, while the bundled Go HTTP middleware forwards the body and the backend parses it normally. This is a deterministic request-body inspection bypass. Suggested severity: **Medium**. Current OWASP CRS includes rule `901340`, which forces fallback inspection and mitigates this path; this report does not claim a bypass of an unmodified current CRS ruleset ### Details The affected component is request-body processor selection in [`internal/corazawaf/transaction.go`](https://github.com/corazawaf/coraza/blob/db9850b2dd8992f97a8cefe08d0cb4edd966a04c/internal/corazawaf/transaction.go#L371-L390). `Transaction.AddRequestHeader` compares the complete lowercased header value using exact equality: ```go case "content-type": val := strings.ToLower(value) if val == "application/x-www-form-urlencoded" { tx.variables.reqbodyProcessor.Set("URLENCODED") } else if strings.HasPrefix(val, "multipart/form-data") { tx.variables.reqbodyProcessor.Set("MULTIPART") } ``` Source: [`internal/corazawaf/transaction.go`, lines 383-390](https://github.com/corazawaf/coraza/blob/db9850b2dd8992f97a8cefe08d0cb4edd966a04c/internal/corazawaf/transaction.go#L383-L3

Products: github.com/corazawaf/coraza, github.com/corazawaf/coraza/v2, github.com/corazawaf/coraza/v3
Affected versions: Not specified
Fixed versions: 3.8.1
CVEs: CVE-2026-114100
Confirmed fixed CVEs: Not specified
Updated in this feed: 31 Oct 2026, 14:08 UTC · Revision 2

Source evidence

Coraza: URL-encoded form Content-Type parameters bypass Coraza body inspection

core-osv · Original source

Published 8 Oct 2026, 17:51 UTC

osv:GHSA-w253-m66g-rx24

github.com/corazawaf/coraza/v3

Fixed versions: 3.8.1

Complete source record

{
  "id": "d69121d9506a4aeda6a98d032fbcf303ee0ab0a0c25e6e05080e8ce7bf156b80",
  "url": "https://osv.dev/vulnerability/GHSA-w253-m66g-rx24",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Coraza: URL-encoded form Content-Type parameters bypass Coraza body inspection",
    "summary": "### Summary Coraza fails to inspect URL-encoded form bodies when their valid `Content-Type` contains a media-type parameter, for example: ```http Content-Type: application/x-www-form-urlencoded; charset=UTF-8 ``` An unauthenticated attacker can use this header to hide the complete form body from custom Coraza rules that inspect `ARGS_POST` or `REQUEST_BODY`, while the bundled Go HTTP middleware forwards the body and the backend parses it normally. This is a deterministic request-body inspection bypass. Suggested severity: **Medium**. Current OWASP CRS includes rule `901340`, which forces fallback inspection and mitigates this path; this report does not claim a bypass of an unmodified current CRS ruleset ### Details The affected component is request-body processor selection in [`internal/corazawaf/transaction.go`](https://github.com/corazawaf/coraza/blob/db9850b2dd8992f97a8cefe08d0cb4edd966a04c/internal/corazawaf/transaction.go#L371-L390). `Transaction.AddRequestHeader` compares the complete lowercased header value using exact equality: ```go case \"content-type\": val := strings.ToLower(value) if val == \"application/x-www-form-urlencoded\" { tx.variables.reqbodyProcessor.Set(\"URLENCODED\") } else if strings.HasPrefix(val, \"multipart/form-data\") { tx.variables.reqbodyProcessor.Set(\"MULTIPART\") } ``` Source: [`internal/corazawaf/transaction.go`, lines 383-390](https://github.com/corazawaf/coraza/blob/db9850b2dd8992f97a8cefe08d0cb4edd966a04c/internal/corazawaf/transaction.go#L383-L3",
    "evidence": "osv:GHSA-w253-m66g-rx24",
    "products": [
      {
        "name": {
          "value": "github.com/corazawaf/coraza/v3",
          "evidence": "/affected/0/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "3.8.1",
            "evidence": "/affected/0/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "medium",
    "structured": {
      "id": "GHSA-w253-m66g-rx24",
      "aliases": [
        "CVE-2026-114100",
        "GHSA-w253-m66g-rx24",
        "GO-2026-6698"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "type": "SEMVER",
              "events": [
                {
                  "introduced": "3.0.4"
                },
                {
                  "fixed": "3.8.1"
                }
              ]
            }
          ],
          "package": {
            "name": "github.com/corazawaf/coraza/v3",
            "purl": "pkg:golang/github.com/corazawaf/coraza/v3",
            "ecosystem": "Go"
          },
          "database_specific": {
            "source": "https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/10/GHSA-w253-m66g-rx24/GHSA-w253-m66g-rx24.json"
          }
        }
      ],
      "modified": "2026-10-21T10:56:44.870639532Z",
      "provider": "osv",
      "references": [
        "https://github.com/corazawaf/coraza/security/advisories/GHSA-w253-m66g-rx24",
        "https://github.com/corazawaf/coraza/commit/3b6241ef895b089c66a59e51068a81cf40986e4d",
        "https://github.com/corazawaf/coraza/commit/a55950ffa161f33a29e14f87d926d7df3b85cc74",
        "https://github.com/corazawaf/coraza/commit/dd100261cf1d2e2b053803a50c9db28dcaaa4b7c",
        "https://github.com/corazawaf/coraza",
        "https://github.com/corazawaf/coraza/releases/tag/v3.8.1"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-20",
          "CWE-436"
        ],
        "severity": "MODERATE",
        "github_reviewed": true,
        "nvd_published_at": null,
        "github_reviewed_at": "2026-10-08T17:51:53Z"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-114100",
        "evidence": "/aliases"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 392967,
  "published_at": "2026-10-08T17:51:53+00:00"
}

Coraza: URL-encoded form Content-Type parameters bypass Coraza body inspection in github.com/corazawaf/coraza

core-osv · Original source

Published 19 Oct 2026, 21:08 UTC

Coraza: URL-encoded form Content-Type parameters bypass Coraza body inspection in github.com/corazawaf/coraza

osv:GO-2026-6698

github.com/corazawaf/coraza

Fixed versions: Not specified

github.com/corazawaf/coraza/v2

Fixed versions: Not specified

github.com/corazawaf/coraza/v3

Fixed versions: 3.8.1

Complete source record

{
  "id": "70f5e091f39a0c61e438d4fcb1d40adb8f6c937eb5f69121dd9c4e26ab174a22",
  "url": "https://osv.dev/vulnerability/GO-2026-6698",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Coraza: URL-encoded form Content-Type parameters bypass Coraza body inspection in github.com/corazawaf/coraza",
    "summary": "Coraza: URL-encoded form Content-Type parameters bypass Coraza body inspection in github.com/corazawaf/coraza",
    "evidence": "osv:GO-2026-6698",
    "products": [
      {
        "name": {
          "value": "github.com/corazawaf/coraza",
          "evidence": "/affected/0/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [],
        "affected_versions": []
      },
      {
        "name": {
          "value": "github.com/corazawaf/coraza/v2",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [],
        "affected_versions": []
      },
      {
        "name": {
          "value": "github.com/corazawaf/coraza/v3",
          "evidence": "/affected/2/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "3.8.1",
            "evidence": "/affected/2/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "GO-2026-6698",
      "aliases": [
        "CVE-2026-114100",
        "GHSA-w253-m66g-rx24",
        "GO-2026-6698"
      ],
      "affected": [
        {
          "ranges": [
            {
              "type": "SEMVER",
              "events": [
                {
                  "introduced": "0"
                }
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          ],
          "package": {
            "name": "github.com/corazawaf/coraza",
            "purl": "pkg:golang/github.com/corazawaf/coraza",
            "ecosystem": "Go"
          },
          "database_specific": {
            "source": "https://vuln.go.dev/ID/GO-2026-6698.json"
          },
          "ecosystem_specific": {}
        },
        {
          "ranges": [
            {
              "type": "SEMVER",
              "events": [
                {
                  "introduced": "0"
                }
              ]
            }
          ],
          "package": {
            "name": "github.com/corazawaf/coraza/v2",
            "purl": "pkg:golang/github.com/corazawaf/coraza/v2",
            "ecosystem": "Go"
          },
          "database_specific": {
            "source": "https://vuln.go.dev/ID/GO-2026-6698.json"
          },
          "ecosystem_specific": {}
        },
        {
          "ranges": [
            {
              "type": "SEMVER",
              "events": [
                {
                  "introduced": "3.0.4"
                },
                {
                  "fixed": "3.8.1"
                }
              ]
            }
          ],
          "package": {
            "name": "github.com/corazawaf/coraza/v3",
            "purl": "pkg:golang/github.com/corazawaf/coraza/v3",
            "ecosystem": "Go"
          },
          "database_specific": {
            "source": "https://vuln.go.dev/ID/GO-2026-6698.json"
          },
          "ecosystem_specific": {}
        }
      ],
      "modified": "2026-10-21T10:56:44.870639532Z",
      "provider": "osv",
      "references": [
        "https://github.com/corazawaf/coraza/security/advisories/GHSA-w253-m66g-rx24",
        "https://github.com/corazawaf/coraza/commit/3b6241ef895b089c66a59e51068a81cf40986e4d",
        "https://github.com/corazawaf/coraza/commit/a55950ffa161f33a29e14f87d926d7df3b85cc74",
        "https://github.com/corazawaf/coraza/commit/dd100261cf1d2e2b053803a50c9db28dcaaa4b7c",
        "https://github.com/corazawaf/coraza/releases/tag/v3.8.1"
      ],
      "provider_metadata": {
        "url": "https://pkg.go.dev/vuln/GO-2026-6698",
        "review_status": "UNREVIEWED"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-114100",
        "evidence": "/aliases"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 392968,
  "published_at": "2026-10-19T21:08:17+00:00"
}