CVE-2026-79658

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 v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
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

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-25 12:16

Updated : 2026-08-31 20:50

NVD link : CVE-2026-79658

Mitre link : CVE-2026-79658

CVE.ORG link : CVE-2026-79658

JSON object : View

Products Affected

No product.

CWE

CWE-400

Uncontrolled Resource Consumption

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