CVE-2026-84428

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{"bugzilla": {"description": "fastify: fastify: Header validation bypass via incomplete schema case normalization", "id": "2528468", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2528468"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.5", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N", "status": "draft"}, "cwe": "CWE-1289", "details": ["A flaw was found in fastify. Due to incomplete case normalization of HTTP header names within a route's header schema, specifically within the JSON Schema Draft 7 dependencies keyword, an unauthenticated remote attacker can bypass intended conditional checks. This allows the attacker to send headers that activate privileged functionality without providing the required authentication headers, leading to an authorization bypass."], "name": "CVE-2026-84428", "public_date": "2026-09-04T10:24:27Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-84428\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-84428\nhttps://cna.openjsf.org/security-advisories.html\nhttps://github.com/fastify/fastify/security/advisories/GHSA-9q9j-q6p8-xq58"], "threat_severity": "Important"}

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