{ "id": "CVE-2021-21274", "sourceIdentifier": "security-advisories@github.com", "published": "2021-02-26T18:15:12.237", "lastModified": "2024-11-21T05:47:54.520", "vulnStatus": "Modified", "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 1.25.0, a malicious homeserver could redirect requests to their .well-known file to a large file. This can lead to a denial of service attack where homeservers will consume significantly more resources when requesting the .well-known file of a malicious homeserver. This affects any server which accepts federation requests from untrusted servers. Issue is resolved in version 1.25.0. As a workaround the `federation_domain_whitelist` setting can be used to restrict the homeservers communicated with over federation." }, { "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 1.25.0, un servidor dom\u00e9stico malicioso pod\u00eda redireccionar las peticiones para su archivo .well-known a un archivo grande. Esto puede conllevar a un ataque de denegaci\u00f3n de servicio en el que los servidores dom\u00e9sticos consumir\u00e1n significativamente m\u00e1s recursos al solicitar el archivo .well-known de un servidor dom\u00e9stico malicioso. Esto afecta a cualquier servidor que acepte peticiones de federaci\u00f3n desde servidores que no sean confiables. El problema es resuelto en versi\u00f3n 1.25.0. Como soluci\u00f3n alternativa, el ajuste de \"federation_domain_whitelist\" puede ser usado para restringir los servidores dom\u00e9sticos que se comunican con la federaci\u00f3n" } ], "metrics": { "cvssMetricV31": [ { "source": "security-advisories@github.com", "type": "Secondary", "cvssData": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L", "baseScore": 4.3, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "LOW" }, "exploitabilityScore": 2.8, "impactScore": 1.4 }, { "source": "nvd@nist.gov", "type": "Primary", "cvssData": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H", "baseScore": 6.5, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH" }, "exploitabilityScore": 2.8, "impactScore": 3.6 } ], "cvssMetricV2": [ { "source": "nvd@nist.gov", "type": "Primary", "cvssData": { "version": "2.0", "vectorString": "AV:N/AC:M/Au:N/C:N/I:N/A:P", "baseScore": 4.3, "accessVector": "NETWORK", "accessComplexity": "MEDIUM", "authentication": "NONE", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "PARTIAL" }, "baseSeverity": "MEDIUM", "exploitabilityScore": 8.6, "impactScore": 2.9, "acInsufInfo": false, "obtainAllPrivilege": false, "obtainUserPrivilege": false, "obtainOtherPrivilege": false, "userInteractionRequired": true } ] }, "weaknesses": [ { "source": "security-advisories@github.com", "type": "Secondary", "description": [ { "lang": "en", "value": "CWE-400" } ] }, { "source": "nvd@nist.gov", "type": "Primary", "description": [ { "lang": "en", "value": "CWE-770" } ] } ], "configurations": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:a:matrix:synapse:*:*:*:*:*:*:*:*", "versionStartIncluding": "0.99.0", "versionEndExcluding": "1.25.0", "matchCriteriaId": "6C16EE11-380E-400F-9A55-6068AAF132D8" } ] } ] }, { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*", "matchCriteriaId": "A930E247-0B43-43CB-98FF-6CE7B8189835" } ] } ] } ], "references": [ { "url": "https://github.com/matrix-org/synapse/commit/ff5c4da1289cb5e097902b3e55b771be342c29d6", "source": "security-advisories@github.com", "tags": [ "Patch", "Third Party Advisory" ] }, { "url": "https://github.com/matrix-org/synapse/pull/8950", "source": "security-advisories@github.com", "tags": [ "Patch", "Third Party Advisory" ] }, { "url": "https://github.com/matrix-org/synapse/releases/tag/v1.25.0", "source": "security-advisories@github.com", "tags": [ "Third Party Advisory" ] }, { "url": "https://github.com/matrix-org/synapse/security/advisories/GHSA-2hwx-mjrm-v3g8", "source": "security-advisories@github.com", "tags": [ "Patch", "Third Party Advisory" ] }, { "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TNNAJOZNMVMXM6AS7RFFKB4QLUJ4IFEY/", "source": "security-advisories@github.com" }, { "url": "https://github.com/matrix-org/synapse/commit/ff5c4da1289cb5e097902b3e55b771be342c29d6", "source": "af854a3a-2127-422b-91ae-364da2661108", "tags": [ "Patch", "Third Party Advisory" ] }, { "url": "https://github.com/matrix-org/synapse/pull/8950", "source": "af854a3a-2127-422b-91ae-364da2661108", "tags": [ "Patch", "Third Party Advisory" ] }, { "url": "https://github.com/matrix-org/synapse/releases/tag/v1.25.0", "source": "af854a3a-2127-422b-91ae-364da2661108", "tags": [ "Third Party Advisory" ] }, { "url": "https://github.com/matrix-org/synapse/security/advisories/GHSA-2hwx-mjrm-v3g8", "source": "af854a3a-2127-422b-91ae-364da2661108", "tags": [ "Patch", "Third Party Advisory" ] }, { "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TNNAJOZNMVMXM6AS7RFFKB4QLUJ4IFEY/", "source": "af854a3a-2127-422b-91ae-364da2661108" } ] }