Vulnerability Monitor

The vendors, products, and vulnerabilities you care about

CVE-2021-20837


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.


Security Impact Summary

This vulnerability carries a CRITICAL severity rating with a CVSS v3.1 score of 9.8, indicating it can be exploited remotely over the network with relatively low complexity without requiring user interaction and does not require pre-existing privileges . The vulnerability impacts confidentiality (data exposure), integrity (unauthorized modifications), and availability (service disruption) for affected systems. Impacting 1 product from sixapart organizations running these solutions should prioritize assessment and patching.

Historical Context

Reported in 2021, this vulnerability emerged during an era marked by increased sophistication in supply chain attacks, cloud infrastructure vulnerabilities, and software-as-a-service (SaaS) security challenges. Security practices during this period emphasized zero-trust architectures, container security, and API protection.


Published

2021-10-26T06:15:06.987

Last Modified

2024-11-21T05:47:15.313

Status

Modified

Source

[email protected]

Severity

CVSSv3.1: 9.8 (CRITICAL)

CVSSv2 Vector

AV:N/AC:L/Au:N/C:P/I:P/A:P

  • Access Vector: NETWORK
  • Access Complexity: LOW
  • Authentication: NONE
  • Confidentiality Impact: PARTIAL
  • Integrity Impact: PARTIAL
  • Availability Impact: PARTIAL
Exploitability Score

10.0

Impact Score

6.4

Weaknesses
  • Type: Primary
    CWE-78

Affected Vendors & Products
Type Vendor Product Version/Range Vulnerable?
Application sixapart movable_type ≤ 1.46 Yes
Application sixapart movable_type ≤ 1.46 Yes
Application sixapart movable_type ≤ 6.3.11 Yes
Application sixapart movable_type ≤ 6.8.2 Yes
Application sixapart movable_type ≤ 6.8.2 Yes
Application sixapart movable_type ≤ 7.8.1 Yes
Application sixapart movable_type ≤ 7.8.1 Yes

References

How SecUtils Interprets This CVE

SecUtils normalizes and enriches National Vulnerability Database (NVD) records by standardizing vendor and product identifiers, aggregating vulnerability metadata from both NVD and MITRE sources, and providing structured context for security teams. For sixapart's affected products, we extract Common Platform Enumeration (CPE) data, Common Weakness Enumeration (CWE) classifications, CVSS severity metrics, and reference data to enable rapid vulnerability prioritization and asset correlation. This record contains no exploit code, proof-of-concept instructions, or attack methodologies—only defensive intelligence necessary for patch management, risk assessment, and security operations.