High severity · published Sep 24, 2021
CVE-2021-40099
An issue was discovered in Concrete CMS through 8.5.5
7.2
CVSS
2.1%
EPSS
No
On KEV
Description
An issue was discovered in Concrete CMS through 8.5.5. Fetching the update json scheme over HTTP leads to remote code execution.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
High
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)2.1% · higher than 81% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CC
Concrete Cms · Concretecms
through 8.5.5 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-40099
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-40099
Release Notes
https://documentation.concretecms.org/developers/introduction/version-history/856-release-notes
Permissions Required
https://hackerone.com/reports/982130
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