CVE-2021-20809

MEDIUM
6.1
CVSS Score
Published: August 26, 2021 at 01:20 AM UTC
Updated: June 17, 2026 at 03:34 AM UTC
1 product affected across 1 vendorMovable Type

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Severity
MEDIUM6.1
Exploit prediction
EPSS 0.9%

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v ≤ 1.44v ≤ 49036.0 ≤ v ≤ 6.8.07.0 ≤ v < 7.8.0
Affected range stops below 7.8.0, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (2)

x_refsource_MISCThird Party Advisory
https://jvn.jp/en/jp/JVN97545738/index.html

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
REQUIRED
Scope
CHANGED
Confidentiality
LOW
Integrity
LOW
Availability
NONE
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-79

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