How severe is CVE-2021-22966?

CVE-2021-22966 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-22966 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-22966?

CVE-2021-22966 affects Concretecms Concrete Cms. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-22966?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-22966 published?

CVE-2021-22966 was published on 2021-11-19 and last updated on 2026-06-17.

CVE-2021-22966

CVE-2021-22966 is a high-severity vulnerability in Concretecms Concrete Cms with a CVSS 3.x base score of 8.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-863.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.5
EPSS exploit prediction: 1% (57th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-863
Affected product: Concretecms Concrete Cms
Published: 2021-11-19
Last modified: 2026-06-17

Description

Privilege escalation from Editor to Admin using Groups in Concrete CMS versions 8.5.6 and below. If a group is granted "view" permissions on the bulkupdate page, then users in that group can escalate to being an administrator with a specially crafted curl. Fixed by adding a check for group permissions before allowing a group to be moved. Concrete CMS Security team CVSS scoring: 7.1 AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:HCredit for discovery: "Adrian Tiron from FORTBRIDGE ( https://www.fortbridge.co.uk/ )"This fix is also in Concrete version 9.0.0

Frequently asked questions

What is CVE-2021-22966?: Privilege escalation from Editor to Admin using Groups in Concrete CMS versions 8.5.6 and below. If a group is granted "view" permissions on the bulkupdate page, then users in that group can escalate to being an administrator with a specially crafted curl. Fixed by adding a check for group permissions before allowing a group to be moved. Concrete CMS Security team CVSS scoring: 7.1 AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:HCredit for discovery: "Adrian Tiron from FORTBRIDGE ( https://www.fortbridge.co.uk/ )"This fix is also in Concrete version 9.0.0
How severe is CVE-2021-22966?: CVE-2021-22966 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-22966 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-22966?: CVE-2021-22966 affects Concretecms Concrete Cms. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-22966?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-22966 published?: CVE-2021-22966 was published on 2021-11-19 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:concretecms:concrete_cms:*:*:*:*:*:*:*:*

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