CVE-2021-29471

{"cve": {"data_type": "CVE", "references": {"reference_data": [{"url": "https://github.com/matrix-org/synapse/releases/tag/v1.33.2", "name": "https://github.com/matrix-org/synapse/releases/tag/v1.33.2", "tags": ["Release Notes", "Third Party Advisory"], "refsource": "MISC"}, {"url": "https://github.com/matrix-org/synapse/security/advisories/GHSA-x345-32rc-8h85", "name": "https://github.com/matrix-org/synapse/security/advisories/GHSA-x345-32rc-8h85", "tags": ["Patch", "Third Party Advisory"], "refsource": "CONFIRM"}, {"url": "https://github.com/matrix-org/synapse/commit/03318a766cac9f8b053db2214d9c332a977d226c", "name": "https://github.com/matrix-org/synapse/commit/03318a766cac9f8b053db2214d9c332a977d226c", "tags": ["Patch", "Third Party Advisory"], "refsource": "MISC"}]}, "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 1.33.2 \"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."}]}, "problemtype": {"problemtype_data": [{"description": [{"lang": "en", "value": "CWE-400"}]}]}, "data_version": "4.0", "CVE_data_meta": {"ID": "CVE-2021-29471", "ASSIGNER": "security-advisories@github.com"}}, "impact": {"baseMetricV2": {"cvssV2": {"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"}, "severity": "MEDIUM", "acInsufInfo": false, "impactScore": 2.9, "obtainAllPrivilege": false, "exploitabilityScore": 10.0, "obtainUserPrivilege": false, "obtainOtherPrivilege": false, "userInteractionRequired": false}, "baseMetricV3": {"cvssV3": {"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}}, "publishedDate": "2021-05-11T15:15Z", "configurations": {"nodes": [{"children": [], "operator": "OR", "cpe_match": [{"cpe23Uri": "cpe:2.3:a:matrix:synapse:*:*:*:*:*:*:*:*", "cpe_name": [], "vulnerable": true, "versionEndExcluding": "1.33.2"}]}], "CVE_data_version": "4.0"}, "lastModifiedDate": "2021-08-02T03:15Z"}