CVE-2026-79658

HIGHPre-NVD 7.57.5—
EchelonGraph scoreHIGH confidence

Score 7.5 from GitHub Security Advisory (severity: HIGH) published 2026-08-25. a secondary CVSS source baseline 7.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 4 sources updated this week
7.5EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 7.5Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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
EG Score
7.5(high)
EG Risk
49(Track)
EG Risk 49/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity75% × 45%
Exploitation0% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
21%
KEV
Not listed

Published

August 25, 2026

Last Modified

August 29, 2026

Advisory Details (2)

Auto-updated Aug 25, 2026
🔬 Proof of concept available. Patch available. Sources: github.
generic

Ech0 before 5.0.1 Denial of Service via Accept-Language | Advisories | VulnCheck

https://www.vulncheck.com/advisories/ech0-before-denial-of-service-via-accept-language
github Patch Available🟡 PoC Available

ParseAcceptLanguage `_` separator bypass enables ~70x CPU amplification via Accept-Language header in i18n.Middleware · Advisory · lin-snow/Ech0 · GitHub

https://github.com/lin-snow/Ech0/security/advisories/GHSA-mqxv-9rm6-w8qc

Vendor Advisories for CVE-2026-79658(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 25× in last 7d / 25× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-08-30 01:22 UTCEPSS rescore
  2. 2026-08-30 01:12 UTCGHSA enrichment
  3. 2026-08-29 12:21 UTCEG score recompute
  4. 2026-08-29 12:20 UTCGHSA enrichment
  5. 2026-08-29 12:00 UTCEG score recompute
  6. 2026-08-29 11:59 UTCGHSA enrichment
  7. 2026-08-29 00:17 UTCEG score recompute
  8. 2026-08-29 00:17 UTCGHSA enrichment
  9. 2026-08-28 21:42 UTCEPSS rescore
  10. 2026-08-28 08:21 UTCGHSA enrichment
  11. 2026-08-27 19:30 UTCEG score recompute
  12. 2026-08-27 19:30 UTCGHSA enrichment
  13. 2026-08-27 14:25 UTCEPSS rescore
  14. 2026-08-27 06:40 UTCGHSA enrichment
  15. 2026-08-26 17:23 UTCEG score recompute
  16. 2026-08-26 17:23 UTCGHSA enrichment
  17. 2026-08-26 16:23 UTCEG score recompute
  18. 2026-08-26 16:23 UTCGHSA enrichment
  19. 2026-08-26 14:47 UTCEPSS rescore
  20. 2026-08-26 13:57 UTCGHSA enrichment
  21. 2026-08-26 01:08 UTCEG score recompute
  22. 2026-08-26 01:08 UTCGHSA enrichment
  23. 2026-08-25 12:17 UTCEG score recompute
  24. 2026-08-25 11:42 UTCEG score recompute
  25. 2026-08-25 11:41 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-79658?
CVE-2026-79658 is a high vulnerability published on August 25, 2026. 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…
When was CVE-2026-79658 disclosed?
CVE-2026-79658 was first published in the National Vulnerability Database on August 25, 2026, with the most recent update on August 29, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-79658 actively exploited?
CVE-2026-79658 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 78.8% of all scored CVEs.
What is the CVSS score of CVE-2026-79658?
CVE-2026-79658 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-79658?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-79658, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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