{"id":"CVE-2021-32821","url":"https://www.cyber-defence.io/tools/cve/CVE-2021-32821","generatedAt":"2026-10-27T23:36:24.655Z","title":"All known versions include a CSS selector parser that is vulnerable to Regular Expression Denial of Service (ReDoS).","description":"MooTools is a collection of JavaScript utilities for JavaScript developers. All known versions include a CSS selector parser that is vulnerable to Regular Expression Denial of Service (ReDoS). An attack requires that an attacker can inject a string into a CSS selector at runtime, which is quite common with e.g. jQuery CSS selectors. No patches are available for this issue.","published":"2023-01-03T17:15:10.000Z","lastModified":"2026-06-17T03:53:42.000Z","status":"Modified","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"3.1","score":7.5,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},"cwe":["CWE-400","CWE-1333"],"affected":["mootools/mootools"],"epss":{"score":0.00651,"percentile":0.50895,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.65%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://securitylab.github.com/advisories/GHSL-2020-345-redos-mootools/","tags":["Exploit","Third Party Advisory"],"source":"security-advisories@github.com"},{"url":"https://securitylab.github.com/advisories/GHSL-2020-345-redos-mootools/","tags":["Exploit","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2021-32821","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}