{"id":"CVE-2021-20809","aliases":["EUVD-2021-8221","GHSA-53cw-v2f6-28h4"],"status":"published","title":"Cross-site scripting vulnerability in Create screens of Entry, Page, and Content Type of Movable...","description":"Cross-site scripting vulnerability in Create screens of Entry, Page, and Content Type of Movable Type (Movable Type 7 r.4903 and earlier (Movable Type 7 Series), Movable Type 6.8.0 and earlier (Movable Type 6 Series), Movable Type Advanced 7 r.4903 and earlier (Movable Type Advanced 7 Series), Movable Type Premium 1.44 and earlier, and Movable Type Premium Advanced 1.44 and earlier) allows remote attackers to inject arbitrary script or HTML via unspecified vectors.","severity":{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-10","score":0.009,"percentile":0.59959,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-79"],"published":"2021-08-26T01:20:35Z","modified":"2026-06-17T03:34:29Z","products":[{"vendor":"six apart ltd.","product":"movable type"},{"vendor":"sixapart","product":"movable_type"}],"references":[{"url":"https://movabletype.org/news/2021/08/mt-780-681-released.html","tags":["x_refsource_MISC","x_transferred","Release Notes","Vendor Advisory"]},{"url":"https://jvn.jp/en/jp/JVN97545738/index.html","tags":["x_refsource_MISC","x_transferred","Third Party Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-20809"},{"url":"https://github.com/advisories/GHSA-53cw-v2f6-28h4"}],"sources":{"cve":[{"id":"CVE-2021-20809","description":"Cross-site scripting vulnerability in Create screens of Entry, Page, and Content Type of Movable Type (Movable Type 7 r.4903 and earlier (Movable Type 7 Series), Movable Type 6.8.0 and earlier (Movable Type 6 Series), Movable Type Advanced 7 r.4903 and earlier (Movable Type Advanced 7 Series), Movable Type Premium 1.44 and earlier, and Movable Type Premium Advanced 1.44 and earlier) allows remote attackers to inject arbitrary script or HTML via unspecified vectors.","status":"published","published":"2021-08-26T01:20:35Z","modified":"2024-08-03T17:53:22.889Z","updated_at":"2026-11-02T14:32:55.905855Z"}],"euvd":[{"id":"EUVD-2021-8221","description":"Cross-site scripting vulnerability in Create screens of Entry, Page, and Content Type of Movable Type (Movable Type 7 r.4903 and earlier (Movable Type 7 Series), Movable Type 6.8.0 and earlier (Movable Type 6 Series), Movable Type Advanced 7 r.4903 and earlier (Movable Type Advanced 7 Series), Movable Type Premium 1.44 and earlier, and Movable Type Premium Advanced 1.44 and earlier) allows remote attackers to inject arbitrary script or HTML via unspecified vectors.","status":"published","published":"2021-08-26T01:20:35Z","modified":"2024-08-03T17:53:22Z","updated_at":"2026-11-03T03:25:07.874589Z"}],"ghsa":[{"id":"GHSA-53cw-v2f6-28h4","title":"Cross-site scripting vulnerability in Create screens of Entry, Page, and Content Type of Movable...","description":"Cross-site scripting vulnerability in Create screens of Entry, Page, and Content Type of Movable Type (Movable Type 7 r.4903 and earlier (Movable Type 7 Series), Movable Type 6.8.0 and earlier (Movable Type 6 Series), Movable Type Advanced 7 r.4903 and earlier (Movable Type Advanced 7 Series), Movable Type Premium 1.44 and earlier, and Movable Type Premium Advanced 1.44 and earlier) allows remote attackers to inject arbitrary script or HTML via unspecified vectors.","status":"published","published":"2022-05-24T19:12:21Z","modified":"2023-01-30T05:01:50Z","cwes":["CWE-79"],"updated_at":"2026-11-02T14:46:29.807452Z"}],"nvd":[{"id":"CVE-2021-20809","description":"Cross-site scripting vulnerability in Create screens of Entry, Page, and Content Type of Movable Type (Movable Type 7 r.4903 and earlier (Movable Type 7 Series), Movable Type 6.8.0 and earlier (Movable Type 6 Series), Movable Type Advanced 7 r.4903 and earlier (Movable Type Advanced 7 Series), Movable Type Premium 1.44 and earlier, and Movable Type Premium Advanced 1.44 and earlier) allows remote attackers to inject arbitrary script or HTML via unspecified vectors.","status":"published","published":"2021-08-26T02:15:11.267Z","modified":"2026-06-17T03:34:29.27Z","cvss":[{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium","assessor":"primary"},{"version":"2.0","score":4.3,"vector":"AV:N/AC:M/Au:N/C:N/I:P/A:N","level":"medium","assessor":"primary"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T14:06:57.67549Z"}]}}