{
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              "content": {
                "id": "CVE-2026-1525",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-03-12T20:44:24.555703Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
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          }
        ],
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          "dateUpdated": "2026-03-12T20:46:13.379Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "collectionURL": "https://github.com/nodejs/undici/",
          "defaultStatus": "unaffected",
          "packageName": "undici",
          "product": "undici",
          "repo": "https://github.com/nodejs/undici/",
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              "status": "affected",
              "version": "\u003c 6.24.0; 7.0.0 \u003c 7.24.0"
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            {
              "status": "unaffected",
              "version": "6.24.0: 7.24.0"
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          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "remediation developer",
          "value": "Matteo Collina"
        },
        {
          "lang": "en",
          "type": "remediation developer",
          "value": "Ulises Gasc\u00f3n"
        }
      ],
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          "lang": "en",
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              "value": "\u003cp\u003eUndici allows duplicate HTTP\u0026nbsp;\u003ccode\u003eContent-Length\u003c/code\u003e\u0026nbsp;headers when they are provided in an array with case-variant names (e.g.,\u0026nbsp;\u003ccode\u003eContent-Length\u003c/code\u003e\u0026nbsp;and\u0026nbsp;\u003ccode\u003econtent-length\u003c/code\u003e). This produces malformed HTTP/1.1 requests with multiple conflicting\u0026nbsp;\u003ccode\u003eContent-Length\u003c/code\u003e\u0026nbsp;values on the wire.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eWho is impacted:\u003c/strong\u003e\u003c/p\u003e\u003cul\u003e\u003cli\u003eApplications using\u0026nbsp;\u003ccode\u003eundici.request()\u003c/code\u003e,\u0026nbsp;\u003ccode\u003eundici.Client\u003c/code\u003e, or similar low-level APIs with headers passed as flat arrays\u003c/li\u003e\u003cli\u003eApplications that accept user-controlled header names without case-normalization\u003c/li\u003e\u003c/ul\u003e\u003cp\u003e\u003cstrong\u003ePotential consequences:\u003c/strong\u003e\u003c/p\u003e\u003cul\u003e\u003cli\u003e\u003cstrong\u003eDenial of Service\u003c/strong\u003e: Strict HTTP parsers (proxies, servers) will reject requests with duplicate\u0026nbsp;\u003ccode\u003eContent-Length\u003c/code\u003e\u0026nbsp;headers (400 Bad Request)\u003c/li\u003e\u003cli\u003e\u003cstrong\u003eHTTP Request Smuggling\u003c/strong\u003e: In deployments where an intermediary and backend interpret duplicate headers inconsistently (e.g., one uses the first value, the other uses the last), this can enable request smuggling attacks leading to ACL bypass, cache poisoning, or credential hijacking\u003c/li\u003e\u003c/ul\u003e"
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        }
      ],
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          "capecId": "CAPEC-33",
          "descriptions": [
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              "lang": "en",
              "value": "CAPEC-33 HTTP Request Smuggling"
            }
          ]
        },
        {
          "capecId": "CAPEC-273",
          "descriptions": [
            {
              "lang": "en",
              "value": "CAPEC-273 HTTP Response Smuggling"
            }
          ]
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "LOW",
            "baseScore": 6.5,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "integrityImpact": "LOW",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L",
            "version": "3.1"
          },
          "format": "CVSS",
          "scenarios": [
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              "lang": "en",
              "value": "GENERAL"
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      "problemTypes": [
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          "descriptions": [
            {
              "cweId": "CWE-444",
              "description": "CWE-444 Inconsistent interpretation of HTTP requests (\u0027HTTP Request/Response smuggling\u0027)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-03-12T19:56:55.092Z",
        "orgId": "ce714d77-add3-4f53-aff5-83d477b104bb",
        "shortName": "openjs"
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        {
          "url": "https://github.com/nodejs/undici/security/advisories/GHSA-2mjp-6q6p-2qxm"
        },
        {
          "url": "https://www.rfc-editor.org/rfc/rfc9110.html#section-8.6"
        },
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          "url": "https://cwe.mitre.org/data/definitions/444.html"
        },
        {
          "url": "https://hackerone.com/reports/3556037"
        },
        {
          "url": "https://cna.openjsf.org/security-advisories.html"
        }
      ],
      "source": {
        "advisory": "GHSA-2mjp-6q6p-2qxm",
        "discovery": "INTERNAL"
      },
      "title": "undici is vulnerable to Inconsistent Interpretation of HTTP Requests (\u0027HTTP Request/Response Smuggling\u0027)",
      "workarounds": [
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          "value": "If upgrading is not immediately possible:\n\n  *  Validate header names: Ensure no duplicate\u00a0Content-Length\u00a0headers (case-insensitive) are present before passing headers to undici\n  *  Use object format: Pass headers as a plain object ({ \u0027content-length\u0027: \u0027123\u0027 }) rather than an array, which naturally deduplicates by key\n  *  Sanitize user input: If headers originate from user input, normalize header names to lowercase and reject duplicates"
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    "assignerOrgId": "ce714d77-add3-4f53-aff5-83d477b104bb",
    "assignerShortName": "openjs",
    "cveId": "CVE-2026-1525",
    "datePublished": "2026-03-12T19:56:55.092Z",
    "dateReserved": "2026-01-28T12:04:51.369Z",
    "dateUpdated": "2026-03-12T20:46:13.379Z",
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