{"id":"CVE-2026-56763","title":"Hono before 4.12.7 allows __proto__ key in parseBody with dot option enabled, permitting specially crafted form field names to create objects with __proto__ properties","summary":"Hono before 4.12.7 allows __proto__ key in parseBody with dot option enabled, permitting specially crafted form field names to create objects with __proto__ properties. When parsed results are merged into regular JavaScript objects using…","severity":"medium","cvss":4.8,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N","cwe":["CWE-1321"],"published":"2026-07-11","updated":"2026-07-11","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-56763","references":[{"url":"https://github.com/honojs/hono/security/advisories/GHSA-v8w9-8mx6-g223","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/hono-prototype-pollution-via-proto-key-in-parsebody-with-dot-option","label":"disclosure@vulncheck.com"}],"tags":["nvd"],"ingestedAt":"2026-07-11T23:16:21.066Z","epss":0.00273,"epssPercentile":0.19926,"slug":"CVE-2026-56763","body":"## Overview\n\nHono before 4.12.7 allows __proto__ key in parseBody with dot option enabled, permitting specially crafted form field names to create objects with __proto__ properties. When parsed results are merged into regular JavaScript objects using unsafe merge patterns, attackers can exploit this to achieve prototype pollution and modify object behavior.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":26,"depthScoreParts":{"impact":26.4,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}