CVE-2021-21333

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This is fixed in version 1.27.0."}], "metrics": [{"cvssV3_1": {"attackComplexity": "HIGH", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 6.1, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "CHANGED", "userInteraction": "REQUIRED", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:N/I:H/A:N", "version": "3.1"}}], "problemTypes": [{"descriptions": [{"cweId": "CWE-74", "description": "CWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')", "lang": "en", "type": "CWE"}]}], "providerMetadata": {"dateUpdated": "2021-08-02T02:06:36.000Z", "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M"}, "references": [{"tags": ["x_refsource_MISC"], "url": "https://github.com/matrix-org/synapse/releases/tag/v1.27.0"}, {"tags": ["x_refsource_MISC"], "url": "https://github.com/matrix-org/synapse/pull/9200"}, {"tags": ["x_refsource_MISC"], "url": "https://github.com/matrix-org/synapse/commit/e54746bdf7d5c831eabe4dcea76a7626f1de73df"}, {"tags": ["x_refsource_CONFIRM"], "url": "https://github.com/matrix-org/synapse/security/advisories/GHSA-c5f8-35qr-q4fm"}, {"name": "FEDORA-2021-a627cfd31e", "tags": ["vendor-advisory", "x_refsource_FEDORA"], "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TNNAJOZNMVMXM6AS7RFFKB4QLUJ4IFEY/"}], "source": {"advisory": "GHSA-c5f8-35qr-q4fm", "discovery": "UNKNOWN"}, "title": "HTML injection in email and account expiry notifications", "x_legacyV4Record": {"CVE_data_meta": {"ASSIGNER": "security-advisories@github.com", "ID": "CVE-2021-21333", "STATE": "PUBLIC", "TITLE": "HTML injection in email and account expiry notifications"}, "affects": {"vendor": {"vendor_data": [{"product": {"product_data": [{"product_name": "synapse", "version": {"version_data": [{"version_value": "< 1.27.0"}]}}]}, "vendor_name": "matrix-org"}]}}, "data_format": "MITRE", "data_type": "CVE", "data_version": "4.0", "description": {"description_data": [{"lang": "eng", "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 1.27.0, the notification emails sent for notifications for missed messages or for an expiring account are subject to HTML injection. In the case of the notification for missed messages, this could allow an attacker to insert forged content into the email. The account expiry feature is not enabled by default and the HTML injection is not controllable by an attacker. This is fixed in version 1.27.0."}]}, "impact": {"cvss": {"attackComplexity": "HIGH", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 6.1, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "CHANGED", "userInteraction": "REQUIRED", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:N/I:H/A:N", "version": "3.1"}}, "problemtype": {"problemtype_data": [{"description": [{"lang": "eng", "value": "CWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')"}]}]}, "references": {"reference_data": [{"name": "https://github.com/matrix-org/synapse/releases/tag/v1.27.0", "refsource": "MISC", "url": "https://github.com/matrix-org/synapse/releases/tag/v1.27.0"}, {"name": "https://github.com/matrix-org/synapse/pull/9200", "refsource": "MISC", "url": "https://github.com/matrix-org/synapse/pull/9200"}, {"name": "https://github.com/matrix-org/synapse/commit/e54746bdf7d5c831eabe4dcea76a7626f1de73df", "refsource": "MISC", "url": "https://github.com/matrix-org/synapse/commit/e54746bdf7d5c831eabe4dcea76a7626f1de73df"}, {"name": "https://github.com/matrix-org/synapse/security/advisories/GHSA-c5f8-35qr-q4fm", "refsource": "CONFIRM", "url": "https://github.com/matrix-org/synapse/security/advisories/GHSA-c5f8-35qr-q4fm"}, {"name": "FEDORA-2021-a627cfd31e", "refsource": "FEDORA", "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/TNNAJOZNMVMXM6AS7RFFKB4QLUJ4IFEY/"}]}, "source": {"advisory": "GHSA-c5f8-35qr-q4fm", "discovery": "UNKNOWN"}}}, "adp": [{"providerMetadata": {"orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2024-08-03T18:09:15.578Z"}, "title": "CVE Program Container", "references": [{"tags": ["x_refsource_MISC", "x_transferred"], "url": "https://github.com/matrix-org/synapse/releases/tag/v1.27.0"}, {"tags": ["x_refsource_MISC", "x_transferred"], "url": "https://github.com/matrix-org/synapse/pull/9200"}, {"tags": ["x_refsource_MISC", "x_transferred"], "url": "https://github.com/matrix-org/synapse/commit/e54746bdf7d5c831eabe4dcea76a7626f1de73df"}, {"tags": ["x_refsource_CONFIRM", "x_transferred"], "url": "https://github.com/matrix-org/synapse/security/advisories/GHSA-c5f8-35qr-q4fm"}, {"name": "FEDORA-2021-a627cfd31e", "tags": ["vendor-advisory", "x_refsource_FEDORA", "x_transferred"], "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TNNAJOZNMVMXM6AS7RFFKB4QLUJ4IFEY/"}]}]}, "cveMetadata": {"assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "assignerShortName": "GitHub_M", "cveId": "CVE-2021-21333", "datePublished": "2021-03-26T20:00:19.000Z", "dateReserved": "2020-12-22T00:00:00.000Z", "dateUpdated": "2024-08-03T18:09:15.578Z", "state": "PUBLISHED"}, "dataType": "CVE_RECORD", "dataVersion": "5.1"}

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{"affected": [{"affectedData": [{"product": "synapse", "vendor": "matrix-org", "versions": [{"status": "affected", "version": "< 1.27.0"}]}], "source": "security-advisories@github.com"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:matrix:synapse:*:*:*:*:*:*:*:*", "matchCriteriaId": "E8EA28E9-E52F-44E4-8B22-A35D16744A0C", "versionEndExcluding": "1.27.0", "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 1.27.0, the notification emails sent for notifications for missed messages or for an expiring account are subject to HTML injection. In the case of the notification for missed messages, this could allow an attacker to insert forged content into the email. The account expiry feature is not enabled by default and the HTML injection is not controllable by an attacker. This is fixed in version 1.27.0."}, {"lang": "es", "value": "Synapse es un servidor dom\u00e9stico de referencia de Matrix escrito en python (paquete pypi matrix-synapse).&#xa0;Matrix es un ecosistema para VoIP y mensajer\u00eda instant\u00e1nea federada abierta.&#xa0;En Synapse versiones anteriores a 1.27.0, los correos electr\u00f3nicos de notificaci\u00f3n enviados para notificaciones de mensajes perdidos o para una cuenta que vence est\u00e1n sujetos a una inyecci\u00f3n de HTML.&#xa0;En el caso de la notificaci\u00f3n de mensajes perdidos, esto podr\u00eda permitir a un atacante insertar contenido forjado en el correo electr\u00f3nico.&#xa0;La funcionalidad expiry de la cuenta no est\u00e1 habilitada por defecto y la inyecci\u00f3n de HTML por un atacante no es controlable .&#xa0;Esto es corregido en la versi\u00f3n 1.27.0."}], "id": "CVE-2021-21333", "lastModified": "2026-06-17T03:35:19.060", "metrics": {"cvssMetricV2": [{"acInsufInfo": false, "baseSeverity": "LOW", "cvssData": {"accessComplexity": "HIGH", "accessVector": "NETWORK", "authentication": "NONE", "availabilityImpact": "NONE", "baseScore": 2.6, "confidentialityImpact": "NONE", "integrityImpact": "PARTIAL", "vectorString": "AV:N/AC:H/Au:N/C:N/I:P/A:N", "version": "2.0"}, "exploitabilityScore": 4.9, "impactScore": 2.9, "obtainAllPrivilege": false, "obtainOtherPrivilege": false, "obtainUserPrivilege": false, "source": "nvd@nist.gov", "type": "Primary", "userInteractionRequired": true}], "cvssMetricV31": [{"cvssData": {"attackComplexity": "HIGH", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 6.1, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "CHANGED", "userInteraction": "REQUIRED", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:N/I:H/A:N", "version": "3.1"}, "exploitabilityScore": 1.6, "impactScore": 4.0, "source": "security-advisories@github.com", "type": "Secondary"}, {"cvssData": {"attackComplexity": "HIGH", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 6.1, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "CHANGED", "userInteraction": "REQUIRED", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:N/I:H/A:N", "version": "3.1"}, "exploitabilityScore": 1.6, "impactScore": 4.0, "source": "nvd@nist.gov", "type": "Primary"}]}, "published": "2021-03-26T20:15:11.953", "references": [{"source": "security-advisories@github.com", "tags": ["Patch", "Third Party Advisory"], "url": "https://github.com/matrix-org/synapse/commit/e54746bdf7d5c831eabe4dcea76a7626f1de73df"}, {"source": "security-advisories@github.com", "tags": ["Patch", "Third Party Advisory"], "url": "https://github.com/matrix-org/synapse/pull/9200"}, {"source": "security-advisories@github.com", "tags": ["Third Party Advisory"], "url": "https://github.com/matrix-org/synapse/releases/tag/v1.27.0"}, {"source": "security-advisories@github.com", "tags": ["Patch", "Third Party Advisory"], "url": "https://github.com/matrix-org/synapse/security/advisories/GHSA-c5f8-35qr-q4fm"}, {"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/e54746bdf7d5c831eabe4dcea76a7626f1de73df"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch", "Third Party Advisory"], "url": "https://github.com/matrix-org/synapse/pull/9200"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Third Party Advisory"], "url": "https://github.com/matrix-org/synapse/releases/tag/v1.27.0"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch", "Third Party Advisory"], "url": "https://github.com/matrix-org/synapse/security/advisories/GHSA-c5f8-35qr-q4fm"}, {"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-74"}], "source": "security-advisories@github.com", "type": "Secondary"}, {"description": [{"lang": "en", "value": "CWE-79"}], "source": "nvd@nist.gov", "type": "Primary"}]}

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