{"cve":"CVE-2021-20088","nvd":{"published":"2021-04-23T18:15:08.097","modified":"2026-06-17T03:33:15.293","status":"Modified","description":"Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') in mootools-more 1.6.0 allows a malicious user to inject properties into Object.prototype.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":8.8},"cwes":["CWE-1321"],"references":["https://github.com/BlackFan/client-side-prototype-pollution/blob/master/pp/mootools-more.md","https://github.com/BlackFan/client-side-prototype-pollution/blob/master/pp/mootools-more.md"],"products":["mootools:mootools-more"],"source":"nvd","synced_at":"2026-10-19T21:17:01.373894544+00:00"},"epss":{"cve":"CVE-2021-20088","score":0.01449,"percentile":0.73362,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-fw45-938v-p26j","url":"https://osv.dev/vulnerability/GHSA-fw45-938v-p26j","summary":"mootools-more vulnerable to prototype pollution","modified":"2024-04-22T23:44:02.534197Z","packages":[{"ecosystem":"npm","name":"mootools-more","purl":"pkg:npm/mootools-more","ranges":["<=1.6.0"],"fixed":[]}]}],"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."]}