HIGH

CVE-2026-61629

nginx ignition has ParseAcceptLanguage `_` separator bypass that enables ~75x CPU amplification via Accept-Language header in i18nMiddleware

CVSS v3

7.5

HIGH

EPSS Score

0.4 %

exploit probability, as of 2026-09-28

CISA KEV

known exploited

Exploitation

—

SSVC status

Description

nginx ignition is a user interface for the nginx web server. In versions 2.29.0 through 2.40.0, the gin i18n middleware in nginx-ignition's API server runs in front of every HTTP request and calls `golang.org/x/text/language.ParseAcceptLanguage` on the raw `Accept-Language` header without imposing any size or shape filter. The underlying parser has quadratic-time behaviour on long lists of malformed language tags. The CVE-2022-32149 guard that golang.org/x/text added in v0.3.8 caps the number of

Technical details

Published: 2026-09-21
Last Modified: 2026-09-21

Frequently asked questions

What is CVE-2026-61629?

Is CVE-2026-61629 actively exploited?

Active exploitation of CVE-2026-61629 has not been confirmed. Its EPSS score was 0.4% on 2026-09-28, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2026-61629?

CVE-2026-61629 has a CVSS v3 base score of 7.5 (HIGH severity).

Is CVE-2026-61629 affecting your environment?

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