CVE-2026-4224 (GCVE-0-2026-4224)

Vulnerability from cvelistv5 – Published: 2026-03-16 17:52 – Updated: 2026-04-08 12:55
VLAI
Title
Stack overflow parsing XML with deeply nested DTD content models
Summary
When an Expat parser with a registered ElementDeclHandler parses an inline document type definition containing a deeply nested content model a C stack overflow occurs.
Severity
6 (Medium)
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
Assigner
PSF
References
Impacted products
Vendor Product Version
Python Software Foundation CPython Affected: 0 , < 3.13.13 (python)
Affected: 3.14.0 , < 3.14.4 (python)
Affected: 3.15.0a1 , < 3.15.0a8 (python)
Create a notification for this product.
Credits
Gil Portnoy Stan Ulbrych Bénédikt Tran Stan Ulbrych
Show details on NVD website
To clipboard 

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-4224",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-03-16T18:20:48.548008Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "problemTypes": [
          {
            "descriptions": [
              {
                "cweId": "CWE-674",
                "description": "CWE-674 Uncontrolled Recursion",
                "lang": "en",
                "type": "CWE"
              }
            ]
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-03-16T18:21:11.567Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      },
      {
        "providerMetadata": {
          "dateUpdated": "2026-03-16T23:08:21.692Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "url": "http://www.openwall.com/lists/oss-security/2026/03/16/4"
          }
        ],
        "title": "CVE Program Container"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "CPython",
          "repo": "https://github.com/python/cpython",
          "vendor": "Python Software Foundation",
          "versions": [
            {
              "lessThan": "3.13.13",
              "status": "affected",
              "version": "0",
              "versionType": "python"
            },
            {
              "lessThan": "3.14.4",
              "status": "affected",
              "version": "3.14.0",
              "versionType": "python"
            },
            {
              "lessThan": "3.15.0a8",
              "status": "affected",
              "version": "3.15.0a1",
              "versionType": "python"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "reporter",
          "value": "Gil Portnoy"
        },
        {
          "lang": "en",
          "type": "remediation developer",
          "value": "Stan Ulbrych"
        },
        {
          "lang": "en",
          "type": "remediation reviewer",
          "value": "B\u00e9n\u00e9dikt Tran"
        },
        {
          "lang": "en",
          "type": "coordinator",
          "value": "Stan Ulbrych"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "When an Expat parser with a registered ElementDeclHandler parses an inline\ndocument type definition containing a deeply nested content model a C stack\noverflow occurs."
            }
          ],
          "value": "When an Expat parser with a registered ElementDeclHandler parses an inline\ndocument type definition containing a deeply nested content model a C stack\noverflow occurs."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "LOW",
            "attackRequirements": "PRESENT",
            "attackVector": "NETWORK",
            "baseScore": 6,
            "baseSeverity": "MEDIUM",
            "exploitMaturity": "NOT_DEFINED",
            "privilegesRequired": "LOW",
            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "valueDensity": "NOT_DEFINED",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "HIGH",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "NONE",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-04-08T12:55:03.693Z",
        "orgId": "28c92f92-d60d-412d-b760-e73465c3df22",
        "shortName": "PSF"
      },
      "references": [
        {
          "tags": [
            "patch"
          ],
          "url": "https://github.com/python/cpython/commit/eb0e8be3a7e11b87d198a2c3af1ed0eccf532768"
        },
        {
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://mail.python.org/archives/list/security-announce@python.org/thread/5M7CGUW3XBRY7II4DK43KF7NQQ3TPZ6R/"
        },
        {
          "tags": [
            "issue-tracking"
          ],
          "url": "https://github.com/python/cpython/issues/145986"
        },
        {
          "tags": [
            "patch"
          ],
          "url": "https://github.com/python/cpython/pull/145987"
        },
        {
          "tags": [
            "patch"
          ],
          "url": "https://github.com/python/cpython/commit/196edfb06a7458377d4d0f4b3cd41724c1f3bd4a"
        },
        {
          "tags": [
            "patch"
          ],
          "url": "https://github.com/python/cpython/commit/e0a8a6da90597a924b300debe045cdb4628ee1f3"
        },
        {
          "tags": [
            "patch"
          ],
          "url": "https://github.com/python/cpython/commit/642865ddf4b232da1f3b1f7abcfa3254c4bfe785"
        },
        {
          "tags": [
            "patch"
          ],
          "url": "https://github.com/python/cpython/commit/af856a7177326ac25d9f66cc6dd28b554d914fee"
        }
      ],
      "source": {
        "discovery": "UNKNOWN"
      },
      "title": "Stack overflow parsing XML with deeply nested DTD content models",
      "x_generator": {
        "engine": "Vulnogram 0.6.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "28c92f92-d60d-412d-b760-e73465c3df22",
    "assignerShortName": "PSF",
    "cveId": "CVE-2026-4224",
    "datePublished": "2026-03-16T17:52:26.639Z",
    "dateReserved": "2026-03-15T18:10:54.886Z",
    "dateUpdated": "2026-04-08T12:55:03.693Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-4224",
      "date": "2026-06-19",
      "epss": "0.00621",
      "percentile": "0.4502"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-4224\",\"sourceIdentifier\":\"cna@python.org\",\"published\":\"2026-03-16T18:16:10.070\",\"lastModified\":\"2026-06-04T19:33:19.660\",\"vulnStatus\":\"Analyzed\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"When an Expat parser with a registered ElementDeclHandler parses an inline\\ndocument type definition containing a deeply nested content model a C stack\\noverflow occurs.\"},{\"lang\":\"es\",\"value\":\"Cuando un analizador Expat con un ElementDeclHandler registrado analiza una definici\u00f3n de tipo de documento en l\u00ednea que contiene un modelo de contenido profundamente anidado, se produce un desbordamiento de pila C.\"}],\"metrics\":{\"cvssMetricV40\":[{\"source\":\"cna@python.org\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"4.0\",\"vectorString\":\"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X\",\"baseScore\":6.0,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"attackRequirements\":\"PRESENT\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"vulnConfidentialityImpact\":\"NONE\",\"vulnIntegrityImpact\":\"NONE\",\"vulnAvailabilityImpact\":\"HIGH\",\"subConfidentialityImpact\":\"NONE\",\"subIntegrityImpact\":\"NONE\",\"subAvailabilityImpact\":\"NONE\",\"exploitMaturity\":\"NOT_DEFINED\",\"confidentialityRequirement\":\"NOT_DEFINED\",\"integrityRequirement\":\"NOT_DEFINED\",\"availabilityRequirement\":\"NOT_DEFINED\",\"modifiedAttackVector\":\"NOT_DEFINED\",\"modifiedAttackComplexity\":\"NOT_DEFINED\",\"modifiedAttackRequirements\":\"NOT_DEFINED\",\"modifiedPrivilegesRequired\":\"NOT_DEFINED\",\"modifiedUserInteraction\":\"NOT_DEFINED\",\"modifiedVulnConfidentialityImpact\":\"NOT_DEFINED\",\"modifiedVulnIntegrityImpact\":\"NOT_DEFINED\",\"modifiedVulnAvailabilityImpact\":\"NOT_DEFINED\",\"modifiedSubConfidentialityImpact\":\"NOT_DEFINED\",\"modifiedSubIntegrityImpact\":\"NOT_DEFINED\",\"modifiedSubAvailabilityImpact\":\"NOT_DEFINED\",\"Safety\":\"NOT_DEFINED\",\"Automatable\":\"NOT_DEFINED\",\"Recovery\":\"NOT_DEFINED\",\"valueDensity\":\"NOT_DEFINED\",\"vulnerabilityResponseEffort\":\"NOT_DEFINED\",\"providerUrgency\":\"NOT_DEFINED\"}}],\"cvssMetricV31\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H\",\"baseScore\":7.5,\"baseSeverity\":\"HIGH\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"NONE\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":3.9,\"impactScore\":3.6}]},\"weaknesses\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-674\"}]}],\"configurations\":[{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:python:python:*:*:*:*:*:*:*:*\",\"versionEndExcluding\":\"3.10.0\",\"matchCriteriaId\":\"B50E99CC-5784-49AD-B11D-6873DE2AC6D3\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:python:python:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"3.13.0\",\"versionEndExcluding\":\"3.13.13\",\"matchCriteriaId\":\"007095D5-A427-40FC-AA54-37477BCC0D06\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:python:python:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"3.14.0\",\"versionEndExcluding\":\"3.14.4\",\"matchCriteriaId\":\"AA3B34C3-1E02-4674-8370-0DD4D24DBE58\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:python:python:3.15.0:alpha1:*:*:*:*:*:*\",\"matchCriteriaId\":\"A3327507-0B1D-4F28-A983-D07A2C8A7696\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:python:python:3.15.0:alpha2:*:*:*:*:*:*\",\"matchCriteriaId\":\"C8AF17F1-A27F-4C98-BA5A-B4319710E8D1\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:python:python:3.15.0:alpha3:*:*:*:*:*:*\",\"matchCriteriaId\":\"24CF56B0-2F4E-42A2-B655-F493AA0A4815\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:python:python:3.15.0:alpha4:*:*:*:*:*:*\",\"matchCriteriaId\":\"7184ABBA-B100-489E-B5C1-1C9EEC0546CA\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:python:python:3.15.0:alpha5:*:*:*:*:*:*\",\"matchCriteriaId\":\"B6D4181B-3E1B-499B-AAB1-50868A6A6AD3\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:python:python:3.15.0:alpha6:*:*:*:*:*:*\",\"matchCriteriaId\":\"A52F6DD2-717D-4E8C-8DB7-00890BC1ABAE\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:python:python:3.15.0:alpha7:*:*:*:*:*:*\",\"matchCriteriaId\":\"8C46C55C-801E-4F86-B669-8E6A12B4AB6F\"}]}]}],\"references\":[{\"url\":\"https://github.com/python/cpython/commit/196edfb06a7458377d4d0f4b3cd41724c1f3bd4a\",\"source\":\"cna@python.org\",\"tags\":[\"Patch\"]},{\"url\":\"https://github.com/python/cpython/commit/642865ddf4b232da1f3b1f7abcfa3254c4bfe785\",\"source\":\"cna@python.org\",\"tags\":[\"Patch\"]},{\"url\":\"https://github.com/python/cpython/commit/af856a7177326ac25d9f66cc6dd28b554d914fee\",\"source\":\"cna@python.org\",\"tags\":[\"Patch\"]},{\"url\":\"https://github.com/python/cpython/commit/e0a8a6da90597a924b300debe045cdb4628ee1f3\",\"source\":\"cna@python.org\",\"tags\":[\"Patch\"]},{\"url\":\"https://github.com/python/cpython/commit/eb0e8be3a7e11b87d198a2c3af1ed0eccf532768\",\"source\":\"cna@python.org\",\"tags\":[\"Patch\"]},{\"url\":\"https://github.com/python/cpython/issues/145986\",\"source\":\"cna@python.org\",\"tags\":[\"Issue Tracking\"]},{\"url\":\"https://github.com/python/cpython/pull/145987\",\"source\":\"cna@python.org\",\"tags\":[\"Patch\"]},{\"url\":\"https://mail.python.org/archives/list/security-announce@python.org/thread/5M7CGUW3XBRY7II4DK43KF7NQQ3TPZ6R/\",\"source\":\"cna@python.org\",\"tags\":[\"Third Party Advisory\"]},{\"url\":\"http://www.openwall.com/lists/oss-security/2026/03/16/4\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\",\"tags\":[\"Mailing List\",\"Third Party Advisory\"]}]}}",
    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CVE Program Container\", \"references\": [{\"url\": \"http://www.openwall.com/lists/oss-security/2026/03/16/4\"}], \"providerMetadata\": {\"orgId\": \"af854a3a-2127-422b-91ae-364da2661108\", \"shortName\": \"CVE\", \"dateUpdated\": \"2026-03-16T23:08:21.692Z\"}}, {\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-4224\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-03-16T18:20:48.548008Z\"}}}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-674\", \"description\": \"CWE-674 Uncontrolled Recursion\"}]}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-03-16T18:19:38.658Z\"}}], \"cna\": {\"title\": \"Stack overflow parsing XML with deeply nested DTD content models\", \"source\": {\"discovery\": \"UNKNOWN\"}, \"credits\": [{\"lang\": \"en\", \"type\": \"reporter\", \"value\": \"Gil Portnoy\"}, {\"lang\": \"en\", \"type\": \"remediation developer\", \"value\": \"Stan Ulbrych\"}, {\"lang\": \"en\", \"type\": \"remediation reviewer\", \"value\": \"B\\u00e9n\\u00e9dikt Tran\"}, {\"lang\": \"en\", \"type\": \"coordinator\", \"value\": \"Stan Ulbrych\"}], \"metrics\": [{\"format\": \"CVSS\", \"cvssV4_0\": {\"Safety\": \"NOT_DEFINED\", \"version\": \"4.0\", \"Recovery\": \"NOT_DEFINED\", \"baseScore\": 6, \"Automatable\": \"NOT_DEFINED\", \"attackVector\": \"NETWORK\", \"baseSeverity\": \"MEDIUM\", \"valueDensity\": \"NOT_DEFINED\", \"vectorString\": \"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N\", \"exploitMaturity\": \"NOT_DEFINED\", \"providerUrgency\": \"NOT_DEFINED\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"attackRequirements\": \"PRESENT\", \"privilegesRequired\": \"LOW\", \"subIntegrityImpact\": \"NONE\", \"vulnIntegrityImpact\": \"NONE\", \"subAvailabilityImpact\": \"NONE\", \"vulnAvailabilityImpact\": \"HIGH\", \"subConfidentialityImpact\": \"NONE\", \"vulnConfidentialityImpact\": \"NONE\", \"vulnerabilityResponseEffort\": \"NOT_DEFINED\"}, \"scenarios\": [{\"lang\": \"en\", \"value\": \"GENERAL\"}]}], \"affected\": [{\"repo\": \"https://github.com/python/cpython\", \"vendor\": \"Python Software Foundation\", \"product\": \"CPython\", \"versions\": [{\"status\": \"affected\", \"version\": \"0\", \"lessThan\": \"3.13.13\", \"versionType\": \"python\"}, {\"status\": \"affected\", \"version\": \"3.14.0\", \"lessThan\": \"3.14.4\", \"versionType\": \"python\"}, {\"status\": \"affected\", \"version\": \"3.15.0a1\", \"lessThan\": \"3.15.0a8\", \"versionType\": \"python\"}], \"defaultStatus\": \"unaffected\"}], \"references\": [{\"url\": \"https://github.com/python/cpython/commit/eb0e8be3a7e11b87d198a2c3af1ed0eccf532768\", \"tags\": [\"patch\"]}, {\"url\": \"https://mail.python.org/archives/list/security-announce@python.org/thread/5M7CGUW3XBRY7II4DK43KF7NQQ3TPZ6R/\", \"tags\": [\"vendor-advisory\"]}, {\"url\": \"https://github.com/python/cpython/issues/145986\", \"tags\": [\"issue-tracking\"]}, {\"url\": \"https://github.com/python/cpython/pull/145987\", \"tags\": [\"patch\"]}, {\"url\": \"https://github.com/python/cpython/commit/196edfb06a7458377d4d0f4b3cd41724c1f3bd4a\", \"tags\": [\"patch\"]}, {\"url\": \"https://github.com/python/cpython/commit/e0a8a6da90597a924b300debe045cdb4628ee1f3\", \"tags\": [\"patch\"]}, {\"url\": \"https://github.com/python/cpython/commit/642865ddf4b232da1f3b1f7abcfa3254c4bfe785\", \"tags\": [\"patch\"]}, {\"url\": \"https://github.com/python/cpython/commit/af856a7177326ac25d9f66cc6dd28b554d914fee\", \"tags\": [\"patch\"]}], \"x_generator\": {\"engine\": \"Vulnogram 0.6.0\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"When an Expat parser with a registered ElementDeclHandler parses an inline\\ndocument type definition containing a deeply nested content model a C stack\\noverflow occurs.\", \"supportingMedia\": [{\"type\": \"text/html\", \"value\": \"When an Expat parser with a registered ElementDeclHandler parses an inline\\ndocument type definition containing a deeply nested content model a C stack\\noverflow occurs.\", \"base64\": false}]}], \"providerMetadata\": {\"orgId\": \"28c92f92-d60d-412d-b760-e73465c3df22\", \"shortName\": \"PSF\", \"dateUpdated\": \"2026-04-08T12:55:03.693Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2026-4224\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-04-08T12:55:03.693Z\", \"dateReserved\": \"2026-03-15T18:10:54.886Z\", \"assignerOrgId\": \"28c92f92-d60d-412d-b760-e73465c3df22\", \"datePublished\": \"2026-03-16T17:52:26.639Z\", \"assignerShortName\": \"PSF\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.