CVE-2021-40109

Description

A SSRF issue was discovered in Concrete CMS through 8.5.5. Users can access forbidden files on their local network. A user with permissions to upload files from external sites can upload a URL that redirects to an internal resource of any file type. The redirect is followed and loads the contents of the file from the redirected-to server. Files of disallowed types can be uploaded.

Category

6.4
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.10%
Vendor Advisory concretecms.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://hackerone.com/reports/1102105 permissions required
https://documentation.concretecms.org/developers/introduction/version-history/856-release-notes release notes vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-40109?
CVE-2021-40109 has been scored as a medium severity vulnerability.
How to fix CVE-2021-40109?
To fix CVE-2021-40109, 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-2021-40109 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-40109 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.
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