{"id":"CVE-2021-20185","url":"https://www.cyber-defence.io/tools/cve/CVE-2021-20185","generatedAt":"2026-10-27T22:31:19.679Z","title":"It was found in Moodle before version 3.10.1, 3.9.4, 3.8.7 and 3.5.16 that messaging did not impose a character limit when sending messages, which could result in client-side (browser) denial of service for users receiving very large messages.","description":"It was found in Moodle before version 3.10.1, 3.9.4, 3.8.7 and 3.5.16 that messaging did not impose a character limit when sending messages, which could result in client-side (browser) denial of service for users receiving very large messages.","published":"2021-01-28T20:15:13.000Z","lastModified":"2026-06-17T03:33:26.000Z","status":"Modified","sourceIdentifier":"secalert@redhat.com","cvss":{"version":"3.1","score":5.3,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"},"cwe":["CWE-400","CWE-770"],"affected":["moodle/moodle"],"epss":{"score":0.01394,"percentile":0.72188,"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":"low","text":"Lower severity and a low EPSS score (1.39%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"https://moodle.org/mod/forum/discuss.php?d=417168","tags":["Patch","Vendor Advisory"],"source":"secalert@redhat.com"},{"url":"https://moodle.org/mod/forum/discuss.php?d=417168","tags":["Patch","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2021-20185","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."}