{"schemaVersion":3,"id":"GHSA-3WCJ-GJVF-FVCH","aliases":[],"status":"published","duplicateOf":null,"title":null,"description":"Duplicate Advisory: Hono vulnerable to Prototype Pollution possible through __proto__ key allowed in parseBody({ dot: true })\n\n## Duplicate Advisory\n\nThis advisory has been withdrawn because it is a duplicate of GHSA-v8w9-8mx6-g223.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.","dates":{"published":"2026-07-11T15:30:23.000Z","modified":"2026-10-02T22:45:04.331Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":6.3,"severity":"medium","version":"4.0","versionLabel":"v4.0","source":"OSV · Npm","vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","computed":true,"selection":"version-preference"},"metrics":[{"version":"4.0","versionLabel":"v4.0","source":"OSV · Npm","score":6.3,"severity":"medium","vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","exploitability":null,"impact":null,"computed":true},{"version":"3.1","versionLabel":"v3.1","source":"OSV · Npm","score":4.8,"severity":"medium","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N","exploitability":5.6,"impact":4.2,"computed":true}]},"epss":{"probability":null,"percentile":null,"severity":"unknown","asOf":null,"change":{"pp":null,"baselineDate":null,"baselineScore":null},"history":[],"last30":[]},"kev":{"state":"not-listed","entries":[],"listedCount":0,"totalCatalogs":3,"catalogs":[{"source":"cisa","label":"CISA","listed":false,"entry":null},{"source":"enisa","label":"ENISA","listed":false,"entry":null},{"source":"circl","label":"CIRCL","listed":false,"entry":null}]},"ransomware":{"state":"none-recorded","sources":[]},"exploits":[],"exploitCount":0,"weaknesses":[],"affected":[{"vendor":"Npm","product":"hono","name":"hono","label":"hono","ecosystem":"Npm","cpePart":null,"purl":"pkg:npm/hono","purlType":"npm","versions":[{"text":"All versions","noFixRecorded":true,"fixedIn":null}],"versionsText":"All versions (No fix recorded)","eol":null,"hubHref":null}],"affectedCount":1,"eol":{"hasEol":false,"count":0},"references":[{"url":"https://github.com/honojs/hono/security/advisories/GHSA-v8w9-8mx6-g223","label":"github.com/honojs/hono/security/advisories/GHSA-v8w9-8mx6-g223","hostname":"github.com","tags":["WEB"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-56763","label":"nvd.nist.gov/vuln/detail/CVE-2026-56763","hostname":"nvd.nist.gov","tags":["Advisory"]},{"url":"https://www.vulncheck.com/advisories/hono-prototype-pollution-via-proto-key-in-parsebody-with-dot-option","label":"www.vulncheck.com/advisories/hono-prototype-pollution-via-proto-key-in-parsebody-with-dot-option","hostname":"www.vulncheck.com","tags":["WEB"]}],"lineage":{"upstream":[],"downstream":["CVE-2026-56763"],"duplicates":[],"related":[]},"timeline":[{"kind":"published","date":"2026-07-11T15:30:23.000Z","label":"Published","detail":"Vulnerability first disclosed.","source":null},{"kind":"modified","date":"2026-10-02T22:45:04.331Z","label":"Last modified","detail":"Vulnerability information updated.","source":null}],"risk":{"score":25,"level":"medium","profile":"Default","thresholds":{"critical":75,"high":50,"medium":25,"low":10}},"meta":{"dataAsOf":"2026-10-21T19:13:39.484Z","stale":false,"partial":false}}