CVE-2026-21393

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.

CVSS v3 5.4 MEDIUM

5.4^/10

CVSS v3 : MEDIUM

Vector : AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

Exploitability : 2.3 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://jvn.jp/en/jp/JVN45405689/
https://movabletype.org/news/2026/02/mt-906-released.html
https://www.sixapart.jp/movabletype/news/2026/02/04-1100.html

Configurations

No configuration.

History

04 Feb 2026, 07:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-02-04 07:16

Updated : 2026-02-04 16:33

NVD link : CVE-2026-21393

Mitre link : CVE-2026-21393

CVE.ORG link : CVE-2026-21393

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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