{"id":"GHSA-3wcj-gjvf-fvch","title":"Duplicate Advisory: Hono vulnerable to Prototype Pollution possible through __proto__ key allowed in parseBody({ dot: true })","summary":"Duplicate Advisory: Hono vulnerable to Prototype Pollution possible through __proto__ key allowed in parseBody({ dot: true })","severity":"medium","cvss":4.8,"cwe":["CWE-1321"],"vendor":"hono","product":"hono","ecosystem":"npm","affected":["hono < 4.12.7"],"published":"2026-07-11","updated":"2026-10-02","sourceUpdated":"2026-10-02T22:36:00Z","source":"GHSA","sourceUrl":"https://github.com/advisories/GHSA-3wcj-gjvf-fvch","references":[{"url":"https://github.com/honojs/hono/security/advisories/GHSA-v8w9-8mx6-g223"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-56763"},{"url":"https://www.vulncheck.com/advisories/hono-prototype-pollution-via-proto-key-in-parsebody-with-dot-option"},{"url":"https://github.com/advisories/GHSA-3wcj-gjvf-fvch"}],"tags":["ghsa","npm"],"ingestedAt":"2026-10-02T23:34:57.406Z","slug":"GHSA-3wcj-gjvf-fvch","body":"## Overview\n\n## Duplicate Advisory\n\nThis advisory has been withdrawn because it is a duplicate of GHSA-v8w9-8mx6-g223. This link is maintained to preserve external references.\n\n## Original Description\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## Affected packages\n\n- `hono < 4.12.7`\n\n## Remediation\n\nRefer to the advisory for the patched release.","depth":"sunlit","depthScore":26,"depthScoreParts":{"impact":26.4,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}