CVE-2021-29471

{"id": "CVE-2021-29471", "cveTags": [], "metrics": {"cvssMetricV2": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"version": "2.0", "baseScore": 5.0, "accessVector": "NETWORK", "vectorString": "AV:N/AC:L/Au:N/C:N/I:N/A:P", "authentication": "NONE", "integrityImpact": "NONE", "accessComplexity": "LOW", "availabilityImpact": "PARTIAL", "confidentialityImpact": "NONE"}, "acInsufInfo": false, "impactScore": 2.9, "baseSeverity": "MEDIUM", "obtainAllPrivilege": false, "exploitabilityScore": 10.0, "obtainUserPrivilege": false, "obtainOtherPrivilege": false, "userInteractionRequired": false}], "cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.3, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "LOW", "privilegesRequired": "NONE", "confidentialityImpact": "NONE"}, "impactScore": 1.4, "exploitabilityScore": 3.9}, {"type": "Secondary", "source": "security-advisories@github.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 3.7, "attackVector": "NETWORK", "baseSeverity": "LOW", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "HIGH", "availabilityImpact": "LOW", "privilegesRequired": "NONE", "confidentialityImpact": "NONE"}, "impactScore": 1.4, "exploitabilityScore": 2.2}]}, "published": "2021-05-11T15:15:08.507", "references": [{"url": "https://github.com/matrix-org/synapse/commit/03318a766cac9f8b053db2214d9c332a977d226c", "tags": ["Patch", "Third Party Advisory"], "source": "security-advisories@github.com"}, {"url": "https://github.com/matrix-org/synapse/releases/tag/v1.33.2", "tags": ["Release Notes", "Third Party Advisory"], "source": "security-advisories@github.com"}, {"url": "https://github.com/matrix-org/synapse/security/advisories/GHSA-x345-32rc-8h85", "tags": ["Patch", "Third Party Advisory"], "source": "security-advisories@github.com"}, {"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TNNAJOZNMVMXM6AS7RFFKB4QLUJ4IFEY/", "source": "security-advisories@github.com"}], "vulnStatus": "Modified", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "CWE-331"}]}, {"type": "Secondary", "source": "security-advisories@github.com", "description": [{"lang": "en", "value": "CWE-400"}]}], "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"}], "lastModified": "2023-11-07T03:32:37.617", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:matrix:synapse:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "CA3C30EA-7826-48F6-9367-5632BE392B50", "versionEndExcluding": "1.33.2"}], "operator": "OR"}]}, {"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "A930E247-0B43-43CB-98FF-6CE7B8189835"}], "operator": "OR"}]}], "sourceIdentifier": "security-advisories@github.com"}