{"api_version":"1","generated_at":"2026-04-22T21:28:35+00:00","cve":"CVE-2023-35944","urls":{"html":"https://cve.report/CVE-2023-35944","api":"https://cve.report/api/cve/CVE-2023-35944.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2023-35944","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2023-35944"},"summary":{"title":"CVE-2023-35944","description":"Envoy is an open source edge and service proxy designed for cloud-native applications. Envoy allows mixed-case schemes in HTTP/2, however, some internal scheme checks are case-sensitive. Prior to versions 1.27.0, 1.26.4, 1.25.9, 1.24.10, and 1.23.12, this can lead to the rejection of requests with mixed-case schemes such as `htTp` or `htTps`, or the bypassing of some requests such as `https` in unencrypted connections. With a fix in versions 1.27.0, 1.26.4, 1.25.9, 1.24.10, and 1.23.12, Envoy will now lowercase scheme values by default, and change the internal scheme checks that were case-sensitive to be case-insensitive. There are no known workarounds for this issue.","state":"PUBLIC","assigner":"security-advisories@github.com","published_at":"2023-07-25 19:15:00","updated_at":"2023-08-02 16:37:00"},"problem_types":["CWE-444"],"metrics":[],"references":[{"url":"https://github.com/envoyproxy/envoy/security/advisories/GHSA-pvgm-7jpg-pw5g","name":"https://github.com/envoyproxy/envoy/security/advisories/GHSA-pvgm-7jpg-pw5g","refsource":"MISC","tags":[],"title":"Incorrect handling of HTTP requests and responses with mixed case schemes in Envoy · Advisory · envoyproxy/envoy · GitHub","mime":"text/html","httpstatus":"200","archivestatus":"404"},{"url":"https://www.cve.org/CVERecord?id=CVE-2023-35944","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2023-35944","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[{"cve_year":"2023","cve_id":"35944","vulnerable":"1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"a","cpe4":"envoyproxy","cpe5":"envoy","cpe6":"*","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"}],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[{"cve":"CVE-2023-35944","qid":"355870","title":"Amazon Linux Security Advisory for ecs-service-connect-agent : ALAS2023-2023-300"},{"cve":"CVE-2023-35944","qid":"356117","title":"Amazon Linux Security Advisory for ecs-service-connect-agent : ALAS2023-2023-344"},{"cve":"CVE-2023-35944","qid":"356246","title":"Amazon Linux Security Advisory for ecs-service-connect-agent : ALASECS-2023-007"},{"cve":"CVE-2023-35944","qid":"356504","title":"Amazon Linux Security Advisory for ecs-service-connect-agent : ALAS2ECS-2023-007"}]},"source_records":{"cve_program":{"data_version":"4.0","data_type":"CVE","data_format":"MITRE","CVE_data_meta":{"ID":"CVE-2023-35944","ASSIGNER":"security-advisories@github.com","STATE":"PUBLIC"},"description":{"description_data":[{"lang":"eng","value":"Envoy is an open source edge and service proxy designed for cloud-native applications. 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There are no known workarounds for this issue."}]},"problemtype":{"problemtype_data":[{"description":[{"lang":"eng","value":"CWE-20: Improper Input Validation","cweId":"CWE-20"}]}]},"affects":{"vendor":{"vendor_data":[{"vendor_name":"envoyproxy","product":{"product_data":[{"product_name":"envoy","version":{"version_data":[{"version_affected":"=","version_value":">= 1.26.0, < 1.26.4"},{"version_affected":"=","version_value":">= 1.25.0, < 1.25.9"},{"version_affected":"=","version_value":">= 1.24.0, < 1.24.10"},{"version_affected":"=","version_value":"< 1.23.12"}]}}]}}]}},"references":{"reference_data":[{"url":"https://github.com/envoyproxy/envoy/security/advisories/GHSA-pvgm-7jpg-pw5g","refsource":"MISC","name":"https://github.com/envoyproxy/envoy/security/advisories/GHSA-pvgm-7jpg-pw5g"}]},"source":{"advisory":"GHSA-pvgm-7jpg-pw5g","discovery":"UNKNOWN"},"impact":{"cvss":[{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":8.2,"baseSeverity":"HIGH","confidentialityImpact":"HIGH","integrityImpact":"LOW","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N","version":"3.1"}]}},"nvd":{"publishedDate":"2023-07-25 19:15:00","lastModifiedDate":"2023-08-02 16:37:00","problem_types":["CWE-444"],"metrics":{"baseMetricV3":{"cvssV3":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"LOW","availabilityImpact":"NONE","baseScore":5.3,"baseSeverity":"MEDIUM"},"exploitabilityScore":3.9,"impactScore":1.4}},"configurations":{"CVE_data_version":"4.0","nodes":[{"operator":"OR","children":[],"cpe_match":[{"vulnerable":true,"cpe23Uri":"cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*","versionStartIncluding":"1.24.0","versionEndExcluding":"1.24.10","cpe_name":[]},{"vulnerable":true,"cpe23Uri":"cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*","versionStartIncluding":"1.25.0","versionEndExcluding":"1.25.9","cpe_name":[]},{"vulnerable":true,"cpe23Uri":"cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*","versionStartIncluding":"1.26.0","versionEndExcluding":"1.26.4","cpe_name":[]},{"vulnerable":true,"cpe23Uri":"cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*","versionStartIncluding":"1.23.0","versionEndExcluding":"1.23.12","cpe_name":[]}]}]}},"legacy_mitre":{"record":null,"notes":[]}}}