{"api_version":"1","generated_at":"2026-11-13T01:07:56+00:00","cve":"CVE-2026-126356","urls":{"html":"https://cve.report/CVE-2026-126356","api":"https://cve.report/api/cve/CVE-2026-126356.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-126356","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-126356"},"summary":{"title":"Hono: `validator('form')` skips validation for `multipart/form-data` requests with extra parameters","description":"Hono is a Web application framework that provides support for any JavaScript runtime. From 4.5.1 until 4.13.16, validator('form') uses a strict whole-header pattern that fails to recognize multipart/form-data when its Content-Type includes another legal parameter or extra whitespace after a semicolon. The validation callback receives an empty object even though c.req.parseBody() or c.req.formData() can still parse and expose all submitted fields to the handler. 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From 4.5.1 until 4.13.16, validator('form') uses a strict whole-header pattern that fails to recognize multipart/form-data when its Content-Type includes another legal parameter or extra whitespace after a semicolon. The validation callback receives an empty object even though c.req.parseBody() or c.req.formData() can still parse and expose all submitted fields to the handler. An unauthenticated client can therefore bypass allow-list or required-field checks when the application relies on the form validator and its callback accepts an empty object. application/x-www-form-urlencoded requests are not affected. This issue is fixed in version 4.13.16.","Type":"Description","Title":"Hono: `validator('form')` skips validation for `multipart/form-d"}]}}}