How severe is CVE-2021-47870?

CVE-2021-47870 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2021-47870 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (14th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-47870?

CVE-2021-47870 affects Get-simple Getsimplecms. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-47870?

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

Does CVE-2021-47870 have an EU (EUVD) identifier?

Yes. CVE-2021-47870 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-3608.

When was CVE-2021-47870 published?

CVE-2021-47870 was published on 2026-01-21 and last updated on 2026-06-17.

CVE-2021-47870

CVE-2021-47870 is a medium-severity vulnerability in Get-simple Getsimplecms with a CVSS 3.x base score of 5.4. 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 5.4)
CVSS v4: 4.8
EPSS exploit prediction: 0% (14th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-3608
Weakness: CWE-79
Affected product: Get-simple Getsimplecms
Published: 2026-01-21
Last modified: 2026-06-17

Description

GetSimple CMS My SMTP Contact Plugin 1.1.2 suffers from a Stored Cross-Site Scripting (XSS) vulnerability. The plugin attempts to sanitize user input using htmlspecialchars(), but this can be bypassed by passing dangerous characters as escaped hex bytes. This allows attackers to inject arbitrary client-side code that executes in the administrator's browser when visiting a malicious page.

Frequently asked questions

What is CVE-2021-47870?: GetSimple CMS My SMTP Contact Plugin 1.1.2 suffers from a Stored Cross-Site Scripting (XSS) vulnerability. The plugin attempts to sanitize user input using htmlspecialchars(), but this can be bypassed by passing dangerous characters as escaped hex bytes. This allows attackers to inject arbitrary client-side code that executes in the administrator's browser when visiting a malicious page.
How severe is CVE-2021-47870?: CVE-2021-47870 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2021-47870 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (14th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-47870?: CVE-2021-47870 affects Get-simple Getsimplecms. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-47870?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2021-47870 have an EU (EUVD) identifier?: Yes. CVE-2021-47870 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-3608.
When was CVE-2021-47870 published?: CVE-2021-47870 was published on 2026-01-21 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:get-simple:getsimplecms:1.1.2:*:*:*:*:*:*:*

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