{"id":"CVE-2026-73547","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-73547","generatedAt":"2026-10-28T05:26:48.481Z","title":"An unauthenticated downstream client can crash the Envoy process when the filter and authorization response use query-parameter mutation.","description":"Envoy is an open source edge and service proxy designed for cloud-native applications. Prior to 1.36.10, 1.37.6, 1.38.4, and 1.39.1, Envoy's ext_authz filter assumes that a request contains a :path pseudoheader when applying query_parameters_to_set or query_parameters_to_remove from an authorization response. A path-less CONNECT request makes request_headers_->Path() return null, and Filter::onComplete dereferences that pointer while parsing the query string. An unauthenticated downstream client can crash the Envoy process when the filter and authorization response use query-parameter mutation. The relevant scope boundary is that the deployment must accept path-less CONNECT and configure ext_authz query-parameter mutation. This issue is fixed in versions 1.36.10, 1.37.6, 1.38.4, and 1.39.1.","published":"2026-09-21T20:17:28.000Z","lastModified":"2026-10-06T15:34:36.000Z","status":"Analyzed","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"3.1","score":7.5,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},"cwe":["CWE-20","CWE-476"],"affected":["envoyproxy/envoy"],"epss":{"score":0.00554,"percentile":0.46045,"date":"2026-10-27","history":[{"date":"2026-09-22","score":0.00827,"percentile":0.55907}]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.55%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[{"kind":"new","label":"New CVE","at":"2026-09-21T20:17:28.000Z","detail":{"score":"7.5","severity":"HIGH","publishedAt":"2026-09-21T20:17:28.230Z"},"summary":"New CVE, high severity (CVSS 7.5)."}],"references":[{"url":"https://github.com/envoyproxy/envoy/commit/064af2e61d0d1c421490d9e3e6e643c5d117ffe4","tags":["Patch"],"source":"security-advisories@github.com"},{"url":"https://github.com/envoyproxy/envoy/commit/5f3b8e9b2b8a787a63202d35bb38820f3e9271fe","tags":["Patch"],"source":"security-advisories@github.com"},{"url":"https://github.com/envoyproxy/envoy/commit/838f8ffd9d7b5217682a22ee33470d4c7afb7e98","tags":["Patch"],"source":"security-advisories@github.com"},{"url":"https://github.com/envoyproxy/envoy/commit/c3170d7c747e51bb8254378ea89afc03d3e71929","tags":["Patch"],"source":"security-advisories@github.com"},{"url":"https://github.com/envoyproxy/envoy/releases/tag/v1.36.10","tags":["Release Notes"],"source":"security-advisories@github.com"},{"url":"https://github.com/envoyproxy/envoy/releases/tag/v1.37.6","tags":["Release Notes"],"source":"security-advisories@github.com"},{"url":"https://github.com/envoyproxy/envoy/releases/tag/v1.38.4","tags":["Release Notes"],"source":"security-advisories@github.com"},{"url":"https://github.com/envoyproxy/envoy/releases/tag/v1.39.1","tags":["Release Notes"],"source":"security-advisories@github.com"},{"url":"https://github.com/envoyproxy/envoy/security/advisories/GHSA-87ph-jqwm-pg6r","tags":["Exploit","Vendor Advisory"],"source":"security-advisories@github.com"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-73547","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}