{"cve":"CVE-2021-21320","nvd":{"published":"2021-03-02T03:15:13.213","modified":"2026-06-17T03:35:17.443","status":"Modified","description":"matrix-react-sdk is an npm package which is a Matrix SDK for React Javascript. In matrix-react-sdk before version 3.15.0, the user content sandbox can be abused to trick users into opening unexpected documents. The content is opened with a `blob` origin that cannot access Matrix user data, so messages and secrets are not at risk. This has been fixed in version 3.15.0.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N","score":4.3},"cwes":["CWE-345"],"references":["https://github.com/matrix-org/matrix-react-sdk/commit/b386f0c73b95ecbb6ea7f8f79c6ff5171a8dedd1","https://github.com/matrix-org/matrix-react-sdk/pull/5657","https://github.com/matrix-org/matrix-react-sdk/security/advisories/GHSA-52mq-6jcv-j79x","https://www.npmjs.com/package/matrix-react-sdk","https://github.com/matrix-org/matrix-react-sdk/commit/b386f0c73b95ecbb6ea7f8f79c6ff5171a8dedd1"],"products":["matrix-react-sdk_project:matrix-react-sdk"],"source":"nvd","synced_at":"2026-10-19T21:15:50.279857260+00:00"},"epss":{"cve":"CVE-2021-21320","score":0.00922,"percentile":0.60335,"date":"2026-11-01"},"kev":null,"osv":[{"id":"GHSA-52mq-6jcv-j79x","url":"https://osv.dev/vulnerability/GHSA-52mq-6jcv-j79x","summary":"User content sandbox can be confused into opening arbitrary documents","modified":"2026-07-08T06:28:20.267888512Z","packages":[{"ecosystem":"npm","name":"matrix-react-sdk","purl":"pkg:npm/matrix-react-sdk","ranges":["<3.15.0"],"fixed":["3.15.0"]}]}],"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."]}