How severe is CVE-2026-7881?

CVE-2026-7881 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2026-7881 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (10th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-7881?

CVE-2026-7881 affects Concretecms Concrete Cms. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-7881?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-7881 have an EU (EUVD) identifier?

Yes. CVE-2026-7881 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-31355.

When was CVE-2026-7881 published?

CVE-2026-7881 was published on 2026-05-21 and last updated on 2026-06-17.

CVE-2026-7881

CVE-2026-7881 is a medium-severity vulnerability in Concretecms Concrete Cms with a CVSS 3.x base score of 4.3. 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-639.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
CVSS v4: 6.3
EPSS exploit prediction: 0% (10th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-31355
Weakness: CWE-639
Affected product: Concretecms Concrete Cms
Published: 2026-05-21
Last modified: 2026-06-17

Description

Concrete CMS 9.5.0 and below is subject to Insecure Direct Object Reference (IDOR) in the Express Entry Detail block via the exEntryID parameter. This IDOR leads to unauthorized access to all Express form submissions. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 6.3 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N. Thanks Tristan Madani for reporting.

Frequently asked questions

What is CVE-2026-7881?: Concrete CMS 9.5.0 and below is subject to Insecure Direct Object Reference (IDOR) in the Express Entry Detail block via the exEntryID parameter. This IDOR leads to unauthorized access to all Express form submissions. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 6.3 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N. Thanks Tristan Madani for reporting.
How severe is CVE-2026-7881?: CVE-2026-7881 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2026-7881 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (10th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-7881?: CVE-2026-7881 affects Concretecms Concrete Cms. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-7881?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-7881 have an EU (EUVD) identifier?: Yes. CVE-2026-7881 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-31355.
When was CVE-2026-7881 published?: CVE-2026-7881 was published on 2026-05-21 and last updated on 2026-06-17.

References

https://documentation.concretecms.org/9-x/developers/introduction/version-history/951-release-notes

Affected products (1)

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

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