{"api_version":"1","generated_at":"2026-06-01T12:26:46+00:00","cve":"CVE-2021-32780","urls":{"html":"https://cve.report/CVE-2021-32780","api":"https://cve.report/api/cve/CVE-2021-32780.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2021-32780","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2021-32780"},"summary":{"title":"CVE-2021-32780","description":"Envoy is an open source L7 proxy and communication bus designed for large modern service oriented architectures. In affected versions Envoy transitions a H/2 connection to the CLOSED state when it receives a GOAWAY frame without any streams outstanding. The connection state is transitioned to DRAINING when it receives a SETTING frame with the SETTINGS_MAX_CONCURRENT_STREAMS parameter set to 0. Receiving these two frames in the same I/O event results in abnormal termination of the Envoy process due to invalid state transition from CLOSED to DRAINING. A sequence of H/2 frames delivered by an untrusted upstream server will result in Denial of Service in the presence of untrusted **upstream** servers. Envoy versions 1.19.1, 1.18.4 contain fixes to stop processing of pending H/2 frames after connection transition to the CLOSED state.","state":"PUBLIC","assigner":"security-advisories@github.com","published_at":"2021-08-24 21:15:00","updated_at":"2022-06-15 15:48:00"},"problem_types":["CWE-754"],"metrics":[],"references":[{"url":"https://www.envoyproxy.io/docs/envoy/v1.19.0/version_history/version_history","name":"https://www.envoyproxy.io/docs/envoy/v1.19.0/version_history/version_history","refsource":"MISC","tags":[],"title":"Version history — envoy tag-v1.19.0 documentation","mime":"text/html","httpstatus":"200","archivestatus":"404"},{"url":"https://github.com/envoyproxy/envoy/security/advisories/GHSA-j374-mjrw-vvp8","name":"https://github.com/envoyproxy/envoy/security/advisories/GHSA-j374-mjrw-vvp8","refsource":"CONFIRM","tags":[],"title":"Incorrect handling of H/2 GOAWAY followed by SETTINGS frames · Advisory · envoyproxy/envoy · GitHub","mime":"text/html","httpstatus":"200","archivestatus":"200"},{"url":"https://www.cve.org/CVERecord?id=CVE-2021-32780","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-32780","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[{"cve_year":"2021","cve_id":"32780","vulnerable":"1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"a","cpe4":"envoyproxy","cpe5":"envoy","cpe6":"*","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"},{"cve_year":"2021","cve_id":"32780","vulnerable":"1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"a","cpe4":"envoyproxy","cpe5":"envoy","cpe6":"1.19.0","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"}],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[{"cve":"CVE-2021-32780","qid":"159555","title":"Oracle Enterprise Linux Security Update for olcne (ELSA-2021-9525)"},{"cve":"CVE-2021-32780","qid":"159556","title":"Oracle Enterprise Linux Security Update for olcne (ELSA-2021-9526)"},{"cve":"CVE-2021-32780","qid":"159558","title":"Oracle Enterprise Linux Security Update for olcne istio istio kubernetes (ELSA-2021-9546)"}]},"source_records":{"cve_program":{"CVE_data_meta":{"ASSIGNER":"security-advisories@github.com","ID":"CVE-2021-32780","STATE":"PUBLIC","TITLE":"Incorrect handling of H/2 GOAWAY followed by SETTINGS frames"},"affects":{"vendor":{"vendor_data":[{"product":{"product_data":[{"product_name":"envoy","version":{"version_data":[{"version_value":">= 1.19.0, < 1.19.1"},{"version_value":">= 1.18.0, < 1.18.4"}]}}]},"vendor_name":"envoyproxy"}]}},"data_format":"MITRE","data_type":"CVE","data_version":"4.0","description":{"description_data":[{"lang":"eng","value":"Envoy is an open source L7 proxy and communication bus designed for large modern service oriented architectures. In affected versions Envoy transitions a H/2 connection to the CLOSED state when it receives a GOAWAY frame without any streams outstanding. The connection state is transitioned to DRAINING when it receives a SETTING frame with the SETTINGS_MAX_CONCURRENT_STREAMS parameter set to 0. Receiving these two frames in the same I/O event results in abnormal termination of the Envoy process due to invalid state transition from CLOSED to DRAINING. A sequence of H/2 frames delivered by an untrusted upstream server will result in Denial of Service in the presence of untrusted **upstream** servers. Envoy versions 1.19.1, 1.18.4 contain fixes to stop processing of pending H/2 frames after connection transition to the CLOSED state."}]},"impact":{"cvss":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":8.6,"baseSeverity":"HIGH","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:H","version":"3.1"}},"problemtype":{"problemtype_data":[{"description":[{"lang":"eng","value":"CWE-754: Improper Check for Unusual or Exceptional Conditions"}]}]},"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-j374-mjrw-vvp8","refsource":"CONFIRM","url":"https://github.com/envoyproxy/envoy/security/advisories/GHSA-j374-mjrw-vvp8"}]},"source":{"advisory":"GHSA-j374-mjrw-vvp8","discovery":"UNKNOWN"}},"nvd":{"publishedDate":"2021-08-24 21:15:00","lastModifiedDate":"2022-06-15 15:48:00","problem_types":["CWE-754"],"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":"1.18.0","versionEndExcluding":"1.18.4","cpe_name":[]}]}]}},"legacy_mitre":{"record":{"CveYear":"2021","CveId":"32780","Ordinal":"208168","Title":"CVE-2021-32780","CVE":"CVE-2021-32780","Year":"2021"},"notes":[{"CveYear":"2021","CveId":"32780","Ordinal":"1","NoteData":"Envoy is an open source L7 proxy and communication bus designed for large modern service oriented architectures. In affected versions Envoy transitions a H/2 connection to the CLOSED state when it receives a GOAWAY frame without any streams outstanding. The connection state is transitioned to DRAINING when it receives a SETTING frame with the SETTINGS_MAX_CONCURRENT_STREAMS parameter set to 0. Receiving these two frames in the same I/O event results in abnormal termination of the Envoy process due to invalid state transition from CLOSED to DRAINING. A sequence of H/2 frames delivered by an untrusted upstream server will result in Denial of Service in the presence of untrusted **upstream** servers. Envoy versions 1.19.1, 1.18.4 contain fixes to stop processing of pending H/2 frames after connection transition to the CLOSED state.","Type":"Description","Title":null},{"CveYear":"2021","CveId":"32780","Ordinal":"2","NoteData":"2021-08-24","Type":"Other","Title":"Published"},{"CveYear":"2021","CveId":"32780","Ordinal":"3","NoteData":"2021-08-24","Type":"Other","Title":"Modified"}]}}}