fkie_cve-2021-29471
Vulnerability from fkie_nvd
Published
2021-05-11 15:15
Modified
2024-11-21 06:01
Severity ?
3.7 (Low) - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
5.3 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Summary
Synapse is a Matrix reference homeserver written in python (pypi package matrix-synapse). Matrix is an ecosystem for open federated Instant Messaging and VoIP. In Synapse before version 1.33.2 "Push rules" can specify conditions under which they will match, including `event_match`, which matches event content against a pattern including wildcards. Certain patterns can cause very poor performance in the matching engine, leading to a denial-of-service when processing moderate length events. The issue is patched in version 1.33.2. A potential workaround might be to prevent users from making custom push rules, by blocking such requests at a reverse-proxy.
References
security-advisories@github.comhttps://github.com/matrix-org/synapse/commit/03318a766cac9f8b053db2214d9c332a977d226cPatch, Third Party Advisory
security-advisories@github.comhttps://github.com/matrix-org/synapse/releases/tag/v1.33.2Release Notes, Third Party Advisory
security-advisories@github.comhttps://github.com/matrix-org/synapse/security/advisories/GHSA-x345-32rc-8h85Patch, Third Party Advisory
security-advisories@github.comhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TNNAJOZNMVMXM6AS7RFFKB4QLUJ4IFEY/
af854a3a-2127-422b-91ae-364da2661108https://github.com/matrix-org/synapse/commit/03318a766cac9f8b053db2214d9c332a977d226cPatch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://github.com/matrix-org/synapse/releases/tag/v1.33.2Release Notes, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://github.com/matrix-org/synapse/security/advisories/GHSA-x345-32rc-8h85Patch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TNNAJOZNMVMXM6AS7RFFKB4QLUJ4IFEY/
Impacted products
Vendor Product Version
matrix synapse *
fedoraproject fedora 34


To clipboard 

{
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:matrix:synapse:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "CA3C30EA-7826-48F6-9367-5632BE392B50",
              "versionEndExcluding": "1.33.2",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    },
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*",
              "matchCriteriaId": "A930E247-0B43-43CB-98FF-6CE7B8189835",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Synapse is a Matrix reference homeserver written in python (pypi package matrix-synapse). Matrix is an ecosystem for open federated Instant Messaging and VoIP. In Synapse before version 1.33.2 \"Push rules\" can specify conditions under which they will match, including `event_match`, which matches event content against a pattern including wildcards. Certain patterns can cause very poor performance in the matching engine, leading to a denial-of-service when processing moderate length events. The issue is patched in version 1.33.2. A potential workaround might be to prevent users from making custom push rules, by blocking such requests at a reverse-proxy."
    },
    {
      "lang": "es",
      "value": "Synapse es un servidor dom\u00e9stico de referencia de Matrix escrito en python (paquete pypi matrix-synapse). Matrix es un ecosistema para VoIP y mensajer\u00eda instant\u00e1nea federada abierta. En Synapse versiones anteriores a 1.33.2, unas \"Push rules\" pueden especificar condiciones bajo las cuales coincidir\u00e1n, incluyendo \"event_match\", que compara el contenido del evento con un patr\u00f3n que incluye comodines. Determinados patrones pueden causar un rendimiento muy deficiente en el motor de coincidencia, conllevando a una denegaci\u00f3n de servicio cuando se procesan eventos de duraci\u00f3n moderada. El problema est\u00e1 parcheado en versi\u00f3n 1.33.2. Una posible soluci\u00f3n alternativa podr\u00eda ser impedir a unos usuarios crear reglas de inserci\u00f3n personalizadas, al bloquear dichas peticiones en un proxy inverso"
    }
  ],
  "id": "CVE-2021-29471",
  "lastModified": "2024-11-21T06:01:11.337",
  "metrics": {
    "cvssMetricV2": [
      {
        "acInsufInfo": false,
        "baseSeverity": "MEDIUM",
        "cvssData": {
          "accessComplexity": "LOW",
          "accessVector": "NETWORK",
          "authentication": "NONE",
          "availabilityImpact": "PARTIAL",
          "baseScore": 5.0,
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "vectorString": "AV:N/AC:L/Au:N/C:N/I:N/A:P",
          "version": "2.0"
        },
        "exploitabilityScore": 10.0,
        "impactScore": 2.9,
        "obtainAllPrivilege": false,
        "obtainOtherPrivilege": false,
        "obtainUserPrivilege": false,
        "source": "nvd@nist.gov",
        "type": "Primary",
        "userInteractionRequired": false
      }
    ],
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "LOW",
          "baseScore": 3.7,
          "baseSeverity": "LOW",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L",
          "version": "3.1"
        },
        "exploitabilityScore": 2.2,
        "impactScore": 1.4,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      },
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "LOW",
          "baseScore": 5.3,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 1.4,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ]
  },
  "published": "2021-05-11T15:15:08.507",
  "references": [
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Patch",
        "Third Party Advisory"
      ],
      "url": "https://github.com/matrix-org/synapse/commit/03318a766cac9f8b053db2214d9c332a977d226c"
    },
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Release Notes",
        "Third Party Advisory"
      ],
      "url": "https://github.com/matrix-org/synapse/releases/tag/v1.33.2"
    },
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Patch",
        "Third Party Advisory"
      ],
      "url": "https://github.com/matrix-org/synapse/security/advisories/GHSA-x345-32rc-8h85"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TNNAJOZNMVMXM6AS7RFFKB4QLUJ4IFEY/"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch",
        "Third Party Advisory"
      ],
      "url": "https://github.com/matrix-org/synapse/commit/03318a766cac9f8b053db2214d9c332a977d226c"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
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        "Third Party Advisory"
      ],
      "url": "https://github.com/matrix-org/synapse/releases/tag/v1.33.2"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch",
        "Third Party Advisory"
      ],
      "url": "https://github.com/matrix-org/synapse/security/advisories/GHSA-x345-32rc-8h85"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TNNAJOZNMVMXM6AS7RFFKB4QLUJ4IFEY/"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-400"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    },
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-331"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}


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