Medium severity · published Sep 27, 2021
CVE-2021-40109
A SSRF issue was discovered in Concrete CMS through 8.5.5
6.4
CVSS
0.5%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 45% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CC
Concrete Cms · Concretecms
before 8.5.6 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-40109
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-40109
Release Notes
https://documentation.concretecms.org/developers/introduction/version-history/856-release-notes
Permissions Required
https://hackerone.com/reports/1102105
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