{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-21876",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-01-08T14:52:48.615550Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-01-08T15:55:33.073Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "coreruleset",
          "vendor": "coreruleset",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 4.22.0"
            },
            {
              "status": "affected",
              "version": "\u003c 3.3.8"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "The OWASP core rule set (CRS) is a set of generic attack detection rules for use with compatible web application firewalls. Prior to versions 4.22.0 and 3.3.8, the current rule 922110 has a bug when processing multipart requests with multiple parts. When the first rule in a chain iterates over a collection (like `MULTIPART_PART_HEADERS`), the capture variables (`TX:0`, `TX:1`) get overwritten with each iteration. Only the last captured value is available to the chained rule, which means malicious charsets in earlier parts can be missed if a later part has a legitimate charset. Versions 4.22.0 and 3.3.8 patch the issue."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 9.3,
            "baseSeverity": "CRITICAL",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "LOW",
            "privilegesRequired": "NONE",
            "scope": "CHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-794",
              "description": "CWE-794: Incomplete Filtering of Multiple Instances of Special Elements",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-01-08T13:55:37.102Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/coreruleset/coreruleset/security/advisories/GHSA-36fv-25j3-r2c5",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/coreruleset/coreruleset/security/advisories/GHSA-36fv-25j3-r2c5"
        },
        {
          "name": "https://github.com/coreruleset/coreruleset/commit/80d80473abf71bd49bf6d3c1ab221e3c74e4eb83",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/coreruleset/coreruleset/commit/80d80473abf71bd49bf6d3c1ab221e3c74e4eb83"
        },
        {
          "name": "https://github.com/coreruleset/coreruleset/commit/9917985de09a6cf38b3261faf9105e909d67a7d6",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/coreruleset/coreruleset/commit/9917985de09a6cf38b3261faf9105e909d67a7d6"
        },
        {
          "name": "https://github.com/coreruleset/coreruleset/releases/tag/v3.3.8",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/coreruleset/coreruleset/releases/tag/v3.3.8"
        },
        {
          "name": "https://github.com/coreruleset/coreruleset/releases/tag/v4.22.0",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/coreruleset/coreruleset/releases/tag/v4.22.0"
        }
      ],
      "source": {
        "advisory": "GHSA-36fv-25j3-r2c5",
        "discovery": "UNKNOWN"
      },
      "title": "OWASP CRS has multipart bypass using multiple content-type parts"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-21876",
    "datePublished": "2026-01-08T13:55:37.102Z",
    "dateReserved": "2026-01-05T17:24:36.927Z",
    "dateUpdated": "2026-01-08T15:55:33.073Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}