{"id":"CVE-2026-21393","aliases":["EUVD-2026-5437","GHSA-343f-q34x-rjhr"],"status":"published","title":"Movable Type contains a stored cross-site scripting vulnerability in Edit Comment. If crafted...","description":"Movable Type contains a stored cross-site scripting vulnerability in Edit Comment. If crafted input is stored by an attacker, arbitrary script may be executed on a logged-in user's web browser. Note that Movable Type 7 series and 8.4 series, which are End-of-Life (EOL), are affected by the vulnerability as well.","severity":{"version":"4.0","score":4.8,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.00237,"percentile":0.14877,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-79"],"published":"2026-02-04T07:02:50Z","modified":"2026-06-17T10:18:37Z","products":[{"vendor":"six apart ltd.","product":"movable type (cloud edition)"},{"vendor":"six apart ltd.","product":"movable type (software edition)"},{"vendor":"six apart ltd.","product":"movable type advanced (software edition)"},{"vendor":"six apart ltd.","product":"movable type premium (advanced edition) (software edition)"},{"vendor":"six apart ltd.","product":"movable type premium (cloud edition)"},{"vendor":"six apart ltd.","product":"movable type premium (software edition)"}],"references":[{"url":"https://movabletype.org/news/2026/02/mt-906-released.html"},{"url":"https://www.sixapart.jp/movabletype/news/2026/02/04-1100.html"},{"url":"https://jvn.jp/en/jp/JVN45405689/"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-21393"},{"url":"https://jvn.jp/en/jp/JVN45405689"},{"url":"https://github.com/advisories/GHSA-343f-q34x-rjhr"}],"sources":{"cve":[{"id":"CVE-2026-21393","description":"Movable Type contains a stored cross-site scripting vulnerability in Edit Comment. If crafted input is stored by an attacker, arbitrary script may be executed on a logged-in user's web browser. Note that Movable Type 7 series and 8.4 series, which are End-of-Life (EOL), are affected by the vulnerability as well.","status":"published","published":"2026-02-04T07:02:50.465Z","modified":"2026-02-04T16:08:26.34Z","cvss":[{"version":"4.0","score":4.8,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N","level":"medium","assessor":"cna"},{"version":"3.0","score":5.4,"vector":"CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T13:41:53.237769Z"}],"euvd":[{"id":"EUVD-2026-5437","description":"Movable Type contains a stored cross-site scripting vulnerability in Edit Comment. If crafted input is stored by an attacker, arbitrary script may be executed on a logged-in user's web browser. Note that Movable Type 7 series and 8.4 series, which are End-of-Life (EOL), are affected by the vulnerability as well.","status":"published","published":"2026-02-04T07:02:50Z","modified":"2026-02-04T16:08:26Z","cvss":[{"version":"4.0","score":4.8,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N","level":"medium"}],"updated_at":"2026-11-02T19:48:44.193176Z"}],"ghsa":[{"id":"GHSA-343f-q34x-rjhr","title":"Movable Type contains a stored cross-site scripting vulnerability in Edit Comment. If crafted...","description":"Movable Type contains a stored cross-site scripting vulnerability in Edit Comment. If crafted input is stored by an attacker, arbitrary script may be executed on a logged-in user's web browser. Note that Movable Type 7 series and 8.4 series, which are End-of-Life (EOL), are affected by the vulnerability as well.","status":"published","published":"2026-02-04T09:30:28Z","modified":"2026-02-04T09:30:35Z","cvss":[{"version":"4.0","score":4.8,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium"},{"version":"3.0","score":5.4,"vector":"CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","level":"medium"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T15:06:01.962776Z"}],"nvd":[{"id":"CVE-2026-21393","description":"Movable Type contains a stored cross-site scripting vulnerability in Edit Comment. If crafted input is stored by an attacker, arbitrary script may be executed on a logged-in user's web browser. Note that Movable Type 7 series and 8.4 series, which are End-of-Life (EOL), are affected by the vulnerability as well.","status":"published","published":"2026-02-04T07:16:01.027Z","modified":"2026-06-17T10:18:37.133Z","cvss":[{"version":"4.0","score":4.8,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium","assessor":"secondary"},{"version":"3.0","score":5.4,"vector":"CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","level":"medium","assessor":"secondary"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T14:12:05.149641Z"}]}}