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Envoy versions 1.19.1, 1.18.4, 1.17.4, 1.16.5 contain fixes to reduce time complexity of resetting HTTP/2 streams. 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As a workaround users may limit the number of simultaneous HTTP/2 dreams for upstream and downstream peers to a low number, i.e. 100."}]},"impact":{"cvss":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"LOW","baseScore":5.8,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"CHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L","version":"3.1"}},"problemtype":{"problemtype_data":[{"description":[{"lang":"eng","value":"CWE-834: Excessive Iteration"}]}]},"references":{"reference_data":[{"name":"https://www.envoyproxy.io/docs/envoy/v1.19.0/version_history/version_history","refsource":"MISC","url":"https://www.envoyproxy.io/docs/envoy/v1.19.0/version_history/version_history"},{"name":"https://github.com/envoyproxy/envoy/security/advisories/GHSA-3xh3-33v5-chcc","refsource":"CONFIRM","url":"https://github.com/envoyproxy/envoy/security/advisories/GHSA-3xh3-33v5-chcc"}]},"source":{"advisory":"GHSA-3xh3-33v5-chcc","discovery":"UNKNOWN"}},"nvd":{"publishedDate":"2021-08-24 21:15:00","lastModifiedDate":"2022-06-15 15:49:00","problem_types":["CWE-834"],"metrics":{"baseMetricV3":{"cvssV3":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH","baseScore":7.5,"baseSeverity":"HIGH"},"exploitabilityScore":3.9,"impactScore":3.6},"baseMetricV2":{"cvssV2":{"version":"2.0","vectorString":"AV:N/AC:L/Au:N/C:N/I:N/A:P","accessVector":"NETWORK","accessComplexity":"LOW","authentication":"NONE","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"PARTIAL","baseScore":5},"severity":"MEDIUM","exploitabilityScore":10,"impactScore":2.9,"acInsufInfo":false,"obtainAllPrivilege":false,"obtainUserPrivilege":false,"obtainOtherPrivilege":false,"userInteractionRequired":false}},"configurations":{"CVE_data_version":"4.0","nodes":[{"operator":"OR","children":[],"cpe_match":[{"vulnerable":true,"cpe23Uri":"cpe:2.3:a:envoyproxy:envoy:1.19.0:*:*:*:*:*:*:*","cpe_name":[]},{"vulnerable":true,"cpe23Uri":"cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*","versionStartIncluding":"1.16.0","versionEndExcluding":"1.16.5","cpe_name":[]},{"vulnerable":true,"cpe23Uri":"cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*","versionStartIncluding":"1.17.0","versionEndExcluding":"1.17.4","cpe_name":[]},{"vulnerable":true,"cpe23Uri":"cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*","versionStartIncluding":"1.18.0","versionEndExcluding":"1.18.4","cpe_name":[]}]}]}},"legacy_mitre":{"record":{"CveYear":"2021","CveId":"32778","Ordinal":"208166","Title":"CVE-2021-32778","CVE":"CVE-2021-32778","Year":"2021"},"notes":[{"CveYear":"2021","CveId":"32778","Ordinal":"1","NoteData":"Envoy is an open source L7 proxy and communication bus designed for large modern service oriented architectures. 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