{"cve":"CVE-2026-84367","nvd":{"published":"2026-09-01T21:18:47.737","modified":"2026-09-09T21:09:13.080","status":"Deferred","description":"joi is a schema description language and data validator for JavaScript. From 16.0.0 until 17.13.5 and 18.2.4, joi's lib/types/keys.js internals.rename() implementation used by object().rename() permits a schema that renames keys with a regular-expression source and a Joi.expression() or Joi.x() target that interpolates the pattern's own match data, combined with { multiple: true }, to derive a target from an attacker-controlled input key. An attacker can send x-__proto__ with an object value, causing the target to render as __proto__ and set the prototype of the object returned by validate() instead of creating an own key. The global Object.prototype is not modified, so the effect is confined to the object returned by that validation call. Static-string targets and schemas using the default { multiple: false } are not affected. This issue is fixed in versions 17.13.5 and 18.2.4.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N","score":3.7},"cwes":["CWE-1321"],"references":["https://github.com/hapijs/joi/commit/162f367aa178d2e1ebec8dc1164e5fe16536ddf6","https://github.com/hapijs/joi/commit/172ececa192feda532b743d77bc9d3e523d19b01","https://github.com/hapijs/joi/pull/3134","https://github.com/hapijs/joi/pull/3135","https://github.com/hapijs/joi/security/advisories/GHSA-gg4h-3hg2-grpc"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:50:50.842544443+00:00"},"epss":{"cve":"CVE-2026-84367","score":0.00389,"percentile":0.33034,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-gg4h-3hg2-grpc","url":"https://osv.dev/vulnerability/GHSA-gg4h-3hg2-grpc","summary":"joi: object().rename() with a template target can set the validated object's prototype","modified":"2026-09-08T21:00:05.097709715Z","packages":[{"ecosystem":"npm","name":"joi","purl":"pkg:npm/joi","ranges":[">=16.0.0 <17.13.5"],"fixed":["17.13.5"]},{"ecosystem":"npm","name":"joi","purl":"pkg:npm/joi","ranges":[">=18.0.0 <18.2.4"],"fixed":["18.2.4"]}]}],"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."]}