What’s Vulnerable › Vulnerabilities

CVE-2021-40099

• Severity: high (CVSS 7.2 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 2.1% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2021-09-24 · updated 2026-06-17

Description

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

Affected products

• Concrete CMS: through 8.5.5

References

• https://documentation.concretecms.org/developers/introduction/version-history/856-release-notes
• https://hackerone.com/reports/982130
• https://documentation.concretecms.org/developers/introduction/version-history/856-release-notes
• https://hackerone.com/reports/982130

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