{"cve":"CVE-2021-23438","nvd":{"published":"2021-09-01T19:15:07.440","modified":"2026-06-17T03:38:45.830","status":"Modified","description":"This affects the package mpath before 0.8.4. A type confusion vulnerability can lead to a bypass of CVE-2018-16490. In particular, the condition ignoreProperties.indexOf(parts[i]) !== -1 returns -1 if parts[i] is ['__proto__']. This is because the method that has been called if the input is an array is Array.prototype.indexOf() and not String.prototype.indexOf(). They behave differently depending on the type of the input.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","score":9.8},"cwes":["CWE-843"],"references":["https://github.com/aheckmann/mpath/commit/89402d2880d4ea3518480a8c9847c541f2d824fc","https://snyk.io/vuln/SNYK-JAVA-ORGWEBJARSNPM-1579548","https://snyk.io/vuln/SNYK-JS-MPATH-1577289","https://github.com/aheckmann/mpath/commit/89402d2880d4ea3518480a8c9847c541f2d824fc","https://snyk.io/vuln/SNYK-JAVA-ORGWEBJARSNPM-1579548"],"products":["mpath_project:mpath"],"source":"nvd","synced_at":"2026-10-19T21:21:57.125947417+00:00"},"epss":{"cve":"CVE-2021-23438","score":0.01723,"percentile":0.77508,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-p92x-r36w-9395","url":"https://osv.dev/vulnerability/GHSA-p92x-r36w-9395","summary":"Type confusion in mpath","modified":"2025-01-14T09:12:14.202017Z","packages":[{"ecosystem":"npm","name":"mpath","purl":"pkg:npm/mpath","ranges":["<0.8.4"],"fixed":["0.8.4"]}]}],"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."]}