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{"cveTags": [], "descriptions": [{"lang": "en", "value": "i18next-http-middleware is a middleware to be used with Node.js web frameworks like express or Fastify and also for Deno. Prior to version 3.9.3, i18next-http-middleware wrote user-controlled language values into the Content-Language response header after passing them through utils.escape(), which is an HTML-entity encoder that does not strip carriage return, line feed, or other control characters. When the application used an older i18next (< 19.5.0) that still exercised the backward-compatibility fallback at LanguageDetector.js:100 or otherwise produced a raw detected value, CRLF sequences in the attacker-controlled lng parameter reached res.setHeader('Content-Language', ...) verbatim. This issue has been patched in version 3.9.3."}], "id": "CVE-2026-41683", "lastModified": "2026-05-12T15:29:40.830", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "LOW", "baseScore": 8.6, "baseSeverity": "HIGH", "confidentialityImpact": "LOW", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:L", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 4.7, "source": "security-advisories@github.com", "type": "Secondary"}]}, "published": "2026-05-08T16:16:11.320", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/i18next/i18next-http-middleware/security/advisories/GHSA-c3h8-g69v-pjrg"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Deferred", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-79"}, {"lang": "en", "value": "CWE-113"}], "source": "security-advisories@github.com", "type": "Primary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,3.9.3)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "cna", "scores": [{"score": 100.0, "source": "cna"}]}, "original": {"product": "i18next-http-middleware", "source": "cna", "vendor": "i18next"}, "product": "i18next-http-middleware", "vendor": "i18next"}], "created": "2026-05-08T19:45:15.201613+00:00", "updated": "2026-05-10T21:25:12.098850+00:00", "vendors": ["i18next", "i18next$PRODUCT$i18next-http-middleware"]}