{"cve":"CVE-2026-48819","nvd":{"published":"2026-07-17T20:17:21.553","modified":"2026-10-24T20:10:00.137","status":"Deferred","description":"Hey API is an ecosystem for turning API specifications into production-ready code. Prior to 0.97.3, dist/clients/core/params.ts ships a runtime template copied into generated SDKs as params.gen.ts, and buildClientParams writes unknown slot-prefixed keys such as $body_, $headers_, $path_, and $query_ directly to the corresponding slot, allowing $query___proto__ alongside a legitimate q field to set params.query through params[\"query\"][\"__proto__\"] = value, call Object.setPrototypeOf(params.query, value), and expose inherited attacker-controlled keys during for..in iteration. This issue is fixed in version 0.97.3.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N","score":4.8},"cwes":["CWE-1321"],"references":["https://github.com/hey-api/hey-api/commit/023909137a15eff9c0263d3bcd116140076b214f","https://github.com/hey-api/hey-api/commit/da321a1529eb3c90d2109da870f514b915a60169","https://github.com/hey-api/hey-api/releases/tag/%40hey-api%2Fopenapi-ts%400.97.3","https://github.com/hey-api/hey-api/security/advisories/GHSA-hhx9-57xq-r5rw","https://github.com/hey-api/hey-api/security/advisories/GHSA-hhx9-57xq-r5rw"],"products":[],"source":"nvd","synced_at":"2026-10-25T17:50:08.599881581+00:00"},"epss":{"cve":"CVE-2026-48819","score":0.00272,"percentile":0.19333,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-hhx9-57xq-r5rw","url":"https://osv.dev/vulnerability/GHSA-hhx9-57xq-r5rw","summary":"@hey-api/openapi-ts's `buildClientParams` template: prototype chain substitution via unknown `$<slot>___proto__` key","modified":"2026-09-10T03:50:52.348190044Z","packages":[{"ecosystem":"npm","name":"@hey-api/openapi-ts","purl":"pkg:npm/%40hey-api/openapi-ts","ranges":["<0.97.3"],"fixed":["0.97.3"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}