CVE-2021-21274

{"cve": {"data_type": "CVE", "references": {"reference_data": [{"url": "https://github.com/matrix-org/synapse/releases/tag/v1.25.0", "name": "https://github.com/matrix-org/synapse/releases/tag/v1.25.0", "tags": ["Third Party Advisory"], "refsource": "MISC"}, {"url": "https://github.com/matrix-org/synapse/commit/ff5c4da1289cb5e097902b3e55b771be342c29d6", "name": "https://github.com/matrix-org/synapse/commit/ff5c4da1289cb5e097902b3e55b771be342c29d6", "tags": ["Patch", "Third Party Advisory"], "refsource": "MISC"}, {"url": "https://github.com/matrix-org/synapse/pull/8950", "name": "https://github.com/matrix-org/synapse/pull/8950", "tags": ["Patch", "Third Party Advisory"], "refsource": "MISC"}, {"url": "https://github.com/matrix-org/synapse/security/advisories/GHSA-2hwx-mjrm-v3g8", "name": "https://github.com/matrix-org/synapse/security/advisories/GHSA-2hwx-mjrm-v3g8", "tags": ["Patch", "Third Party Advisory"], "refsource": "CONFIRM"}, {"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/TNNAJOZNMVMXM6AS7RFFKB4QLUJ4IFEY/", "name": "FEDORA-2021-a627cfd31e", "tags": ["Mailing List", "Third Party Advisory"], "refsource": "FEDORA"}]}, "data_format": "MITRE", "description": {"description_data": [{"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."}]}, "problemtype": {"problemtype_data": [{"description": [{"lang": "en", "value": "CWE-770"}]}]}, "data_version": "4.0", "CVE_data_meta": {"ID": "CVE-2021-21274", "ASSIGNER": "security-advisories@github.com"}}, "impact": {"baseMetricV2": {"cvssV2": {"version": "2.0", "baseScore": 4.3, "accessVector": "NETWORK", "vectorString": "AV:N/AC:M/Au:N/C:N/I:N/A:P", "authentication": "NONE", "integrityImpact": "NONE", "accessComplexity": "MEDIUM", "availabilityImpact": "PARTIAL", "confidentialityImpact": "NONE"}, "severity": "MEDIUM", "acInsufInfo": false, "impactScore": 2.9, "obtainAllPrivilege": false, "exploitabilityScore": 8.6, "obtainUserPrivilege": false, "obtainOtherPrivilege": false, "userInteractionRequired": true}, "baseMetricV3": {"cvssV3": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 6.5, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/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"}, "impactScore": 3.6, "exploitabilityScore": 2.8}}, "publishedDate": "2021-02-26T18:15Z", "configurations": {"nodes": [{"children": [], "operator": "OR", "cpe_match": [{"cpe23Uri": "cpe:2.3:a:matrix:synapse:*:*:*:*:*:*:*:*", "cpe_name": [], "vulnerable": true, "versionEndExcluding": "1.25.0", "versionStartIncluding": "0.99.0"}]}, {"children": [], "operator": "OR", "cpe_match": [{"cpe23Uri": "cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*", "cpe_name": [], "vulnerable": true}]}], "CVE_data_version": "4.0"}, "lastModifiedDate": "2022-10-24T20:49Z"}