How severe is CVE-2021-43810?

CVE-2021-43810 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-43810 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (92nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-43810?

CVE-2021-43810 affects Admidio. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-43810?

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-2021-43810 published?

CVE-2021-43810 was published on 2021-12-07 and last updated on 2026-06-17.

CVE-2021-43810

CVE-2021-43810 is a high-severity vulnerability in Admidio 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-79.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 4.3
EPSS exploit prediction: 6% (92nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Admidio
Published: 2021-12-07
Last modified: 2026-06-17

Description

Admidio is a free open source user management system for websites of organizations and groups. A cross-site scripting vulnerability is present in Admidio prior to version 4.0.12. The Reflected XSS vulnerability occurs because redirect.php does not properly validate the value of the url parameter. Through this vulnerability, an attacker is capable to execute malicious scripts. This issue is patched in version 4.0.12.

Frequently asked questions

What is CVE-2021-43810?: Admidio is a free open source user management system for websites of organizations and groups. A cross-site scripting vulnerability is present in Admidio prior to version 4.0.12. The Reflected XSS vulnerability occurs because redirect.php does not properly validate the value of the url parameter. Through this vulnerability, an attacker is capable to execute malicious scripts. This issue is patched in version 4.0.12.
How severe is CVE-2021-43810?: CVE-2021-43810 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-43810 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (92nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-43810?: CVE-2021-43810 affects Admidio. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-43810?: 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-2021-43810 published?: CVE-2021-43810 was published on 2021-12-07 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:admidio:admidio:*:*:*:*:*:*:*:*

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