CVE-2021-40099: High severity ConcreteCMS Concrete CMS vulnerability

Published Sep 24, 2021
·
Updated

An issue was discovered in Concrete CMS through 8.5.5. Fetching the update json scheme over HTTP leads to remote code execution.

Affected Software

1 affected component
ConcreteCMS Concrete CMS<=8.5.5

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade Concrete CMS to a version that resolves this vulnerability.

    Fixed in 8.5.5
  2. Compensating control

    Prevent use of HTTP for fetching the update JSON scheme (block/disable HTTP and require HTTPS) to mitigate remote code execution.

Event History

Sep 24, 2021
CVE Published
via MITRE·02:58 PM
Data Sourced
via MITRE·02:58 PM
Description
Data Sourced
via NVD·03:15 PM
DescriptionSeverityAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2021-40099?

CVE-2021-40099 has a high severity rating due to its potential for remote code execution.

2

How do I fix CVE-2021-40099?

To fix CVE-2021-40099, update Concrete CMS to version 8.5.6 or later.

3

What systems are affected by CVE-2021-40099?

CVE-2021-40099 affects Concrete CMS versions up to and including 8.5.5.

4

What type of vulnerability is CVE-2021-40099?

CVE-2021-40099 is categorized as a remote code execution vulnerability.

5

How can I check if my Concrete CMS is affected by CVE-2021-40099?

You can check your Concrete CMS version in the admin dashboard to see if it is at or below 8.5.5.

Contact

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