CVE-2021-4235 (GCVE-0-2021-4235)

Vulnerability from cvelistv5 – Published: 2022-12-27 21:13 – Updated: 2025-04-11 16:25
VLAI?
Summary
Due to unbounded alias chasing, a maliciously crafted YAML file can cause the system to consume significant system resources. If parsing user input, this may be used as a denial of service vector.
Severity ?
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
CWE
  • CWE 400: Uncontrolled Resource Consumption
Assigner
Go
References
Impacted products
Vendor Product Version
gopkg.in/yaml.v2 gopkg.in/yaml.v2 Affected: 0 , < 2.2.3 (semver)
Create a notification for this product.
Credits
@simonferquel
Show details on NVD website
To clipboard 

{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2024-08-03T17:23:09.096Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://github.com/go-yaml/yaml/pull/375"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://github.com/go-yaml/yaml/commit/bb4e33bf68bf89cad44d386192cbed201f35b241"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://pkg.go.dev/vuln/GO-2021-0061"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://lists.debian.org/debian-lts-announce/2023/07/msg00001.html"
          }
        ],
        "title": "CVE Program Container"
      },
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "LOW",
              "attackVector": "LOCAL",
              "availabilityImpact": "HIGH",
              "baseScore": 5.5,
              "baseSeverity": "MEDIUM",
              "confidentialityImpact": "NONE",
              "integrityImpact": "NONE",
              "privilegesRequired": "NONE",
              "scope": "UNCHANGED",
              "userInteraction": "REQUIRED",
              "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2021-4235",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2025-04-11T16:24:34.544009Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2025-04-11T16:25:11.371Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "collectionURL": "https://pkg.go.dev",
          "defaultStatus": "unaffected",
          "packageName": "gopkg.in/yaml.v2",
          "product": "gopkg.in/yaml.v2",
          "programRoutines": [
            {
              "name": "decoder.unmarshal"
            },
            {
              "name": "Decoder.Decode"
            },
            {
              "name": "Unmarshal"
            },
            {
              "name": "UnmarshalStrict"
            }
          ],
          "vendor": "gopkg.in/yaml.v2",
          "versions": [
            {
              "lessThan": "2.2.3",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        },
        {
          "collectionURL": "https://pkg.go.dev",
          "defaultStatus": "affected",
          "packageName": "github.com/go-yaml/yaml",
          "product": "github.com/go-yaml/yaml",
          "programRoutines": [
            {
              "name": "decoder.unmarshal"
            },
            {
              "name": "Decoder.Decode"
            },
            {
              "name": "Unmarshal"
            },
            {
              "name": "UnmarshalStrict"
            }
          ],
          "vendor": "github.com/go-yaml/yaml"
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "@simonferquel"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Due to unbounded alias chasing, a maliciously crafted YAML file can cause the system to consume significant system resources. If parsing user input, this may be used as a denial of service vector."
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "description": "CWE 400: Uncontrolled Resource Consumption",
              "lang": "en"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2023-07-05T23:06:18.281Z",
        "orgId": "1bb62c36-49e3-4200-9d77-64a1400537cc",
        "shortName": "Go"
      },
      "references": [
        {
          "url": "https://github.com/go-yaml/yaml/pull/375"
        },
        {
          "url": "https://github.com/go-yaml/yaml/commit/bb4e33bf68bf89cad44d386192cbed201f35b241"
        },
        {
          "url": "https://pkg.go.dev/vuln/GO-2021-0061"
        },
        {
          "url": "https://lists.debian.org/debian-lts-announce/2023/07/msg00001.html"
        }
      ],
      "title": "Denial of service in gopkg.in/yaml.v2"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "1bb62c36-49e3-4200-9d77-64a1400537cc",
    "assignerShortName": "Go",
    "cveId": "CVE-2021-4235",
    "datePublished": "2022-12-27T21:13:42.393Z",
    "dateReserved": "2022-07-29T18:56:20.415Z",
    "dateUpdated": "2025-04-11T16:25:11.371Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1",
  "vulnerability-lookup:meta": {
    "fkie_nvd": {
      "configurations": "[{\"nodes\": [{\"operator\": \"OR\", \"negate\": false, \"cpeMatch\": [{\"vulnerable\": true, \"criteria\": \"cpe:2.3:a:yaml_project:yaml:*:*:*:*:*:go:*:*\", \"versionEndExcluding\": \"2.2.3\", \"matchCriteriaId\": \"6ADB4662-19BA-4FB2-88FB-0D8309DE5DB0\"}]}]}]",
      "descriptions": "[{\"lang\": \"en\", \"value\": \"Due to unbounded alias chasing, a maliciously crafted YAML file can cause the system to consume significant system resources. If parsing user input, this may be used as a denial of service vector.\"}, {\"lang\": \"es\", \"value\": \"Debido a la b\\u00fasqueda ilimitada de alias, un archivo YAML creado con fines malintencionados puede hacer que el sistema consuma importantes recursos. Si se analiza la entrada del usuario, esto se puede utilizar como un vector de denegaci\\u00f3n de servicio.\"}]",
      "id": "CVE-2021-4235",
      "lastModified": "2024-11-21T06:37:12.307",
      "metrics": "{\"cvssMetricV31\": [{\"source\": \"nvd@nist.gov\", \"type\": \"Primary\", \"cvssData\": {\"version\": \"3.1\", \"vectorString\": \"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H\", \"baseScore\": 5.5, \"baseSeverity\": \"MEDIUM\", \"attackVector\": \"LOCAL\", \"attackComplexity\": \"LOW\", \"privilegesRequired\": \"NONE\", \"userInteraction\": \"REQUIRED\", \"scope\": \"UNCHANGED\", \"confidentialityImpact\": \"NONE\", \"integrityImpact\": \"NONE\", \"availabilityImpact\": \"HIGH\"}, \"exploitabilityScore\": 1.8, \"impactScore\": 3.6}]}",
      "published": "2022-12-27T22:15:11.960",
      "references": "[{\"url\": \"https://github.com/go-yaml/yaml/commit/bb4e33bf68bf89cad44d386192cbed201f35b241\", \"source\": \"security@golang.org\", \"tags\": [\"Patch\", \"Third Party Advisory\"]}, {\"url\": \"https://github.com/go-yaml/yaml/pull/375\", \"source\": \"security@golang.org\", \"tags\": [\"Exploit\", \"Patch\", \"Third Party Advisory\"]}, {\"url\": \"https://lists.debian.org/debian-lts-announce/2023/07/msg00001.html\", \"source\": \"security@golang.org\"}, {\"url\": \"https://pkg.go.dev/vuln/GO-2021-0061\", \"source\": \"security@golang.org\", \"tags\": [\"Third Party Advisory\"]}, {\"url\": \"https://github.com/go-yaml/yaml/commit/bb4e33bf68bf89cad44d386192cbed201f35b241\", \"source\": \"af854a3a-2127-422b-91ae-364da2661108\", \"tags\": [\"Patch\", \"Third Party Advisory\"]}, {\"url\": \"https://github.com/go-yaml/yaml/pull/375\", \"source\": \"af854a3a-2127-422b-91ae-364da2661108\", \"tags\": [\"Exploit\", \"Patch\", \"Third Party Advisory\"]}, {\"url\": \"https://lists.debian.org/debian-lts-announce/2023/07/msg00001.html\", \"source\": \"af854a3a-2127-422b-91ae-364da2661108\"}, {\"url\": \"https://pkg.go.dev/vuln/GO-2021-0061\", \"source\": \"af854a3a-2127-422b-91ae-364da2661108\", \"tags\": [\"Third Party Advisory\"]}]",
      "sourceIdentifier": "security@golang.org",
      "vulnStatus": "Modified",
      "weaknesses": "[{\"source\": \"nvd@nist.gov\", \"type\": \"Primary\", \"description\": [{\"lang\": \"en\", \"value\": \"NVD-CWE-noinfo\"}]}]"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2021-4235\",\"sourceIdentifier\":\"security@golang.org\",\"published\":\"2022-12-27T22:15:11.960\",\"lastModified\":\"2025-04-11T17:15:35.497\",\"vulnStatus\":\"Modified\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"Due to unbounded alias chasing, a maliciously crafted YAML file can cause the system to consume significant system resources. If parsing user input, this may be used as a denial of service vector.\"},{\"lang\":\"es\",\"value\":\"Debido a la b\u00fasqueda ilimitada de alias, un archivo YAML creado con fines malintencionados puede hacer que el sistema consuma importantes recursos. Si se analiza la entrada del usuario, esto se puede utilizar como un vector de denegaci\u00f3n de servicio.\"}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H\",\"baseScore\":5.5,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"REQUIRED\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"NONE\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":1.8,\"impactScore\":3.6},{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H\",\"baseScore\":5.5,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"REQUIRED\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"NONE\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":1.8,\"impactScore\":3.6}]},\"weaknesses\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"description\":[{\"lang\":\"en\",\"value\":\"NVD-CWE-noinfo\"}]}],\"configurations\":[{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:yaml_project:yaml:*:*:*:*:*:go:*:*\",\"versionEndExcluding\":\"2.2.3\",\"matchCriteriaId\":\"6ADB4662-19BA-4FB2-88FB-0D8309DE5DB0\"}]}]}],\"references\":[{\"url\":\"https://github.com/go-yaml/yaml/commit/bb4e33bf68bf89cad44d386192cbed201f35b241\",\"source\":\"security@golang.org\",\"tags\":[\"Patch\",\"Third Party Advisory\"]},{\"url\":\"https://github.com/go-yaml/yaml/pull/375\",\"source\":\"security@golang.org\",\"tags\":[\"Exploit\",\"Patch\",\"Third Party Advisory\"]},{\"url\":\"https://lists.debian.org/debian-lts-announce/2023/07/msg00001.html\",\"source\":\"security@golang.org\"},{\"url\":\"https://pkg.go.dev/vuln/GO-2021-0061\",\"source\":\"security@golang.org\",\"tags\":[\"Third Party Advisory\"]},{\"url\":\"https://github.com/go-yaml/yaml/commit/bb4e33bf68bf89cad44d386192cbed201f35b241\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\",\"tags\":[\"Patch\",\"Third Party Advisory\"]},{\"url\":\"https://github.com/go-yaml/yaml/pull/375\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\",\"tags\":[\"Exploit\",\"Patch\",\"Third Party Advisory\"]},{\"url\":\"https://lists.debian.org/debian-lts-announce/2023/07/msg00001.html\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\"},{\"url\":\"https://pkg.go.dev/vuln/GO-2021-0061\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\",\"tags\":[\"Third Party Advisory\"]}]}}",
    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CVE Program Container\", \"references\": [{\"url\": \"https://github.com/go-yaml/yaml/pull/375\", \"tags\": [\"x_transferred\"]}, {\"url\": \"https://github.com/go-yaml/yaml/commit/bb4e33bf68bf89cad44d386192cbed201f35b241\", \"tags\": [\"x_transferred\"]}, {\"url\": \"https://pkg.go.dev/vuln/GO-2021-0061\", \"tags\": [\"x_transferred\"]}, {\"url\": \"https://lists.debian.org/debian-lts-announce/2023/07/msg00001.html\", \"tags\": [\"x_transferred\"]}], \"providerMetadata\": {\"orgId\": \"af854a3a-2127-422b-91ae-364da2661108\", \"shortName\": \"CVE\", \"dateUpdated\": \"2024-08-03T17:23:09.096Z\"}}, {\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"cvssV3_1\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 5.5, \"attackVector\": \"LOCAL\", \"baseSeverity\": \"MEDIUM\", \"vectorString\": \"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H\", \"integrityImpact\": \"NONE\", \"userInteraction\": \"REQUIRED\", \"attackComplexity\": \"LOW\", \"availabilityImpact\": \"HIGH\", \"privilegesRequired\": \"NONE\", \"confidentialityImpact\": \"NONE\"}}, {\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2021-4235\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"poc\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2025-04-11T16:24:34.544009Z\"}}}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2025-04-11T16:25:04.788Z\"}}], \"cna\": {\"title\": \"Denial of service in gopkg.in/yaml.v2\", \"credits\": [{\"lang\": \"en\", \"value\": \"@simonferquel\"}], \"affected\": [{\"vendor\": \"gopkg.in/yaml.v2\", \"product\": \"gopkg.in/yaml.v2\", \"versions\": [{\"status\": \"affected\", \"version\": \"0\", \"lessThan\": \"2.2.3\", \"versionType\": \"semver\"}], \"packageName\": \"gopkg.in/yaml.v2\", \"collectionURL\": \"https://pkg.go.dev\", \"defaultStatus\": \"unaffected\", \"programRoutines\": [{\"name\": \"decoder.unmarshal\"}, {\"name\": \"Decoder.Decode\"}, {\"name\": \"Unmarshal\"}, {\"name\": \"UnmarshalStrict\"}]}, {\"vendor\": \"github.com/go-yaml/yaml\", \"product\": \"github.com/go-yaml/yaml\", \"packageName\": \"github.com/go-yaml/yaml\", \"collectionURL\": \"https://pkg.go.dev\", \"defaultStatus\": \"affected\", \"programRoutines\": [{\"name\": \"decoder.unmarshal\"}, {\"name\": \"Decoder.Decode\"}, {\"name\": \"Unmarshal\"}, {\"name\": \"UnmarshalStrict\"}]}], \"references\": [{\"url\": \"https://github.com/go-yaml/yaml/pull/375\"}, {\"url\": \"https://github.com/go-yaml/yaml/commit/bb4e33bf68bf89cad44d386192cbed201f35b241\"}, {\"url\": \"https://pkg.go.dev/vuln/GO-2021-0061\"}, {\"url\": \"https://lists.debian.org/debian-lts-announce/2023/07/msg00001.html\"}], \"descriptions\": [{\"lang\": \"en\", \"value\": \"Due to unbounded alias chasing, a maliciously crafted YAML file can cause the system to consume significant system resources. If parsing user input, this may be used as a denial of service vector.\"}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"description\": \"CWE 400: Uncontrolled Resource Consumption\"}]}], \"providerMetadata\": {\"orgId\": \"1bb62c36-49e3-4200-9d77-64a1400537cc\", \"shortName\": \"Go\", \"dateUpdated\": \"2023-07-05T23:06:18.281Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2021-4235\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2025-04-11T16:25:11.371Z\", \"dateReserved\": \"2022-07-29T18:56:20.415Z\", \"assignerOrgId\": \"1bb62c36-49e3-4200-9d77-64a1400537cc\", \"datePublished\": \"2022-12-27T21:13:42.393Z\", \"assignerShortName\": \"Go\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.1"
    }
  }
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Sightings

Author Source Type Date

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.