{"id":"CVE-2021-32764","url":"https://www.cyber-defence.io/tools/cve/CVE-2021-32764","generatedAt":"2026-10-27T23:42:30.824Z","title":"In Discourse versions 2.7.5 and prior, parsing and rendering of YouTube Oneboxes can be susceptible to XSS attacks.","description":"Discourse is an open-source discussion platform. In Discourse versions 2.7.5 and prior, parsing and rendering of YouTube Oneboxes can be susceptible to XSS attacks. This vulnerability only affects sites which have modified or disabled Discourse's default Content Security Policy. The issue is patched in `stable` version 2.7.6, `beta` version 2.8.0.beta3, and `tests-passed` version 2.8.0.beta3. As a workaround, ensure that the Content Security Policy is enabled, and has not been modified in a way which would make it more vulnerable to XSS attacks.","published":"2021-07-15T21:15:09.000Z","lastModified":"2026-06-17T03:53:35.000Z","status":"Modified","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"3.1","score":5.4,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N"},"cwe":["CWE-79"],"affected":["discourse/discourse"],"epss":{"score":0.00545,"percentile":0.45443,"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 (0.55%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"https://github.com/discourse/discourse/security/advisories/GHSA-9x4c-29xg-56hw","tags":["Third Party Advisory"],"source":"security-advisories@github.com"},{"url":"https://github.com/discourse/discourse/security/advisories/GHSA-9x4c-29xg-56hw","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2021-32764","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."}