Incomplete control character validation in http.cookies

{
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "cveMetadata": {
    "cveId": "CVE-2026-3644",
    "assignerOrgId": "28c92f92-d60d-412d-b760-e73465c3df22",
    "assignerShortName": "PSF",
    "dateUpdated": "2026-03-16T18:25:55.021Z",
    "dateReserved": "2026-03-06T16:13:09.289Z",
    "datePublished": "2026-03-16T17:37:31.344Z",
    "state": "PUBLISHED"
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        "shortName": "PSF",
        "dateUpdated": "2026-03-16T17:45:23.093Z"
      },
      "title": "Incomplete control character validation in http.cookies",
      "descriptions": [
        {
          "lang": "en",
          "value": "The fix for CVE-2026-0672, which rejected control characters in http.cookies.Morsel, was incomplete. The Morsel.update(), |= operator, and unpickling paths were not patched, allowing control characters to bypass input validation. Additionally, BaseCookie.js_output() lacked the output validation applied to BaseCookie.output().",
          "supportingMedia": [
            {
              "type": "text/html",
              "base64": false,
              "value": "The fix for CVE-2026-0672, which rejected control characters in http.cookies.Morsel, was incomplete. The Morsel.update(), |= operator, and unpickling paths were not patched, allowing control characters to bypass input validation. Additionally, BaseCookie.js_output() lacked the output validation applied to BaseCookie.output()."
            }
          ]
        }
      ],
      "affected": [
        {
          "vendor": "Python Software Foundation",
          "product": "CPython",
          "modules": [
            "http.cookies"
          ],
          "repo": "https://github.com/python/cpython",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "0",
              "status": "affected",
              "versionType": "python",
              "lessThan": "3.15.0"
            }
          ]
        }
      ],
      "references": [
        {
          "url": "https://mail.python.org/archives/list/security-announce@python.org/thread/H6CADMBCDRFGWCMOXWUIHFJNV43GABJ7/",
          "tags": [
            "vendor-advisory"
          ]
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        {
          "url": "https://github.com/python/cpython/commit/57e88c1cf95e1481b94ae57abe1010469d47a6b4",
          "tags": [
            "patch"
          ]
        },
        {
          "url": "https://github.com/python/cpython/issues/145599",
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            "issue-tracking"
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        },
        {
          "url": "https://github.com/python/cpython/pull/145600",
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          "url": "https://github.com/python/cpython/commit/62ceb396fcbe69da1ded3702de586f4072b590dd",
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      "credits": [
        {
          "lang": "en",
          "value": "Stan Ulbrych",
          "type": "coordinator"
        },
        {
          "lang": "en",
          "value": "Stan Ulbrych",
          "type": "remediation developer"
        },
        {
          "lang": "en",
          "value": "Victor Stinner",
          "type": "remediation reviewer"
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        {
          "lang": "en",
          "value": "Seth Larson",
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        {
          "lang": "en",
          "value": "Vyom Yadav",
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    "adp": [
      {
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          "shortName": "CISA-ADP",
          "dateUpdated": "2026-03-16T18:25:55.021Z"
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        "title": "CISA ADP Vulnrichment",
        "problemTypes": [
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