How severe is CVE-2021-27581?

CVE-2021-27581 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-27581 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-27581?

CVE-2021-27581 affects Kentico Kentico Cms. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-27581?

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

When was CVE-2021-27581 published?

CVE-2021-27581 was published on 2021-03-05 and last updated on 2026-06-17.

CVE-2021-27581

CVE-2021-27581 is a critical-severity vulnerability in Kentico Kentico Cms with a CVSS 3.x base score of 9.8. 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-89.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 2% (73rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-89
Affected product: Kentico Kentico Cms
Published: 2021-03-05
Last modified: 2026-06-17

Description

The Blog module in Kentico CMS 5.5 R2 build 5.5.3996 allows SQL injection via the tagname parameter.

Frequently asked questions

What is CVE-2021-27581?: The Blog module in Kentico CMS 5.5 R2 build 5.5.3996 allows SQL injection via the tagname parameter.
How severe is CVE-2021-27581?: CVE-2021-27581 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-27581 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-27581?: CVE-2021-27581 affects Kentico Kentico Cms. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-27581?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-27581 published?: CVE-2021-27581 was published on 2021-03-05 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:kentico:kentico_cms:5.5:r2:build_5.5.3996:*:*:*:*:*

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