Vulnerability record · CVE-2026-79658 · published 25 August 2026
CVE-2026-79658: Uncontrolled resource consumption vulnerability
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).
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).
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:
References
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Related vulnerabilities
Same products first, then exploited flaws of the same weakness class.
Source: NIST National Vulnerability Database (record CVE-2026-79658), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.