How severe is CVE-2021-27237?

CVE-2021-27237 has a CVSS 3.x base score of 4.8, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2021-27237 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-2021-27237?

CVE-2021-27237 affects Blackcat-cms Blackcat Cms. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-27237?

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

When was CVE-2021-27237 published?

CVE-2021-27237 was published on 2021-02-16 and last updated on 2026-06-17.

CVE-2021-27237

CVE-2021-27237 is a medium-severity vulnerability in Blackcat-cms Blackcat Cms with a CVSS 3.x base score of 4.8. 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-79.

Key facts

Severity: Medium (CVSS 3.x base score 4.8)
CVSS v2: 3.5
EPSS exploit prediction: 1% (57th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Blackcat-cms Blackcat Cms
Published: 2021-02-16
Last modified: 2026-06-17

Description

The admin panel in BlackCat CMS 1.3.6 allows stored XSS (by an admin) via the Display Name field to backend/preferences/ajax_save.php.

Frequently asked questions

What is CVE-2021-27237?: The admin panel in BlackCat CMS 1.3.6 allows stored XSS (by an admin) via the Display Name field to backend/preferences/ajax_save.php.
How severe is CVE-2021-27237?: CVE-2021-27237 has a CVSS 3.x base score of 4.8, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2021-27237 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-2021-27237?: CVE-2021-27237 affects Blackcat-cms Blackcat Cms. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-27237?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-27237 published?: CVE-2021-27237 was published on 2021-02-16 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:blackcat-cms:blackcat_cms:1.3.6:*:*:*:*:*:*:*

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