CVE-2021-20837

Public Exploit

Description

Movable Type 7 r.5002 and earlier (Movable Type 7 Series), Movable Type 6.8.2 and earlier (Movable Type 6 Series), Movable Type Advanced 7 r.5002 and earlier (Movable Type Advanced 7 Series), Movable Type Advanced 6.8.2 and earlier (Movable Type Advanced 6 Series), Movable Type Premium 1.46 and earlier, and Movable Type Premium Advanced 1.46 and earlier allow remote attackers to execute arbitrary OS commands via unspecified vectors. Note that all versions of Movable Type 4.0 or later including unsupported (End-of-Life, EOL) versions are also affected by this vulnerability.

Category

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 93.76% Top 5%
Vendor Advisory movabletype.org
Affected: Six Apart Ltd. Movable Type
Published at:
Updated at:

References

Link Tags
https://movabletype.org/news/2021/10/mt-782-683-released.html release notes vendor advisory
https://jvn.jp/en/jp/JVN41119755/index.html third party advisory
http://packetstormsecurity.com/files/164705/Movable-Type-7-r.5002-XMLRPC-API-Remote-Command-Injection.html exploit vdb entry third party advisory
http://packetstormsecurity.com/files/164818/Movable-Type-7-r.5002-XMLRPC-API-Remote-Command-Injection.html vdb entry third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-20837?
CVE-2021-20837 has been scored as a critical severity vulnerability.
How to fix CVE-2021-20837?
To fix CVE-2021-20837, 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-2021-20837 being actively exploited in the wild?
It is possible that CVE-2021-20837 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~94% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-20837?
CVE-2021-20837 affects Six Apart Ltd. Movable Type.
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