{"id":"CVE-2026-79658","revision":"01addcc143424584949b8932c73c3ee6","records":[{"revision":"01addcc143424584949b8932c73c3ee6","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-79658","aliases":[],"title":"Ech0 before 5.0.1 Denial of Service via Accept-Language","description":"Ech0 before 5.0.1 does not impose any size or shape limit on the Accept-Language header processed by its i18n middleware, which runs on every HTTP request. The header is passed unfiltered to go-i18n's NewLocalizer, which internally calls golang.org/x/text/language.ParseAcceptLanguage. The CVE-2022-32149 mitigation in x/text caps '-' characters but not '_' characters, which the parser aliases to '-', allowing quadratic-time parsing to be triggered with a large header (up to Go's default 1 MiB) built from underscore separators. An unauthenticated attacker can send such requests to consume roughly 1.5 seconds of CPU each, and concurrent requests can saturate a multi-core server (denial of service).","state":0,"publishedAt":"2026-08-25T11:33:23.319+00:00","modifiedAt":"2026-10-08T15:25:11.723+00:00","affected":[{"ecosystem":"Vendor product","name":"Ech0","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"lin-snow\",\n                    \"product\": \"Ech0\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"packageURL\": \"pkg:golang/github.com/lin-snow/ech0\",\n                    \"versions\": [\n                        {\n                            \"version\": \"0\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"semver\",\n                            \"lessThan\": \"5.0.1\"\n                        },\n                        {\n                            \"version\": \"5.0.1\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","score":8.7,"severity":"HIGH"},{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5,"severity":"HIGH"}],"references":["https://github.com/lin-snow/Ech0/security/advisories/GHSA-mqxv-9rm6-w8qc","https://www.vulncheck.com/advisories/ech0-before-denial-of-service-via-accept-language"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-79658","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-79658","identifiers":["CVE-2026-79658"]},"retained":false,"historicalAffected":[]}],"coverage":[]}