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.

Category

6.1
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.35%
Vendor Advisory movabletype.org
Affected: Six Apart Ltd. Movable Type
Published at:
Updated at:

References

Link Tags
https://movabletype.org/news/2021/08/mt-780-681-released.html release notes vendor advisory
https://jvn.jp/en/jp/JVN97545738/index.html third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-20809?
CVE-2021-20809 has been scored as a medium severity vulnerability.
How to fix CVE-2021-20809?
To fix CVE-2021-20809, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-20809 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-20809 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-20809?
CVE-2021-20809 affects Six Apart Ltd. Movable Type.
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