CVE-2021-22969
mediumpriority · track · 21EPSS 0.009 · 58 %ileEUUSEPSS · scored 2026-10-28
Concrete CMS (formerly concrete5) versions below 8.5.7 has a SSRF mitigation bypass using DNS Rebind attack giving an attacker the ability to fetch cloud IAAS (ex AWS) IAM keys.To fix this Concrete CMS no longer allows downloads from the local network and specifies the validated IP when downloading rather than relying on DNS.Discoverer: Adrian Tiron from FORTBRIDGE ( https://www.fortbridge.co.uk/ )The Concrete CMS team gave this a CVSS 3.1 score of 3.5 AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:N/A:N . Please note that Cloud IAAS provider mis-configurations are not Concrete CMS vulnerabilities. A mitigation for this vulnerability is to make sure that the IMDS configurations are according to a cloud provider's best practices.This fix is also in Concrete version 9.0.0
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (3)
Products and version ranges known to be affected.
- n/a https://github.com/concrete5/concrete5≤ Affected version Concrete CMS (concrete5) 8.5.6 and below. Fixed in Concrete CMS version 8.5.7 and 9.0.0enisa_euvdEU
advisories (1)
Vendor and ecosystem advisories describing this.
- GHSA-mcxr-fx5f-96qqServer-Side Request Forgery in Concrete CMS2021-11-23ghsa · osvUS
Concrete CMS (formerly concrete5) versions below 8.5.7 has a SSRF mitigation bypass using DNS Rebind attack giving an attacker the ability to fetch cloud IAAS (ex AWS) IAM keys.To fix this Concrete CMS no longer allows downloads from the local network and specifies the validated IP when downloading rather than relying on DNS.Discoverer.
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (8)
External citations — patches, advisories, analysis.
- https://documentation.concretecms.org/developers/introduction/version-history/857-release-notescnnvd
- https://hackerone.com/reports/1350444Patchcnnvd
- https://hackerone.com/reports/1369312cnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2021-22969cnnvd
- https://documentation.concretecms.org/developers/introduction/version-history/857-release-notesenisa_euvd
- https://hackerone.com/reports/1369312enisa_euvd
- https://documentation.concretecms.org/developers/introduction/version-history/857-release-notesRelease NotesVendor Advisorynvd
- https://hackerone.com/reports/1369312Permissions Requirednvd
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