How severe is CVE-2021-4073?

CVE-2021-4073 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-2021-4073 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 7% (93rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-4073?

CVE-2021-4073 affects Metagauss Registrationmagic. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-4073?

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-2021-4073 published?

CVE-2021-4073 was published on 2021-12-14 and last updated on 2026-06-17.

CVE-2021-4073

CVE-2021-4073 is a critical-severity vulnerability in Metagauss Registrationmagic 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-287.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 6.8
EPSS exploit prediction: 7% (93rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Metagauss Registrationmagic
Published: 2021-12-14
Last modified: 2026-06-17

Description

The RegistrationMagic WordPress plugin made it possible for unauthenticated users to log in as any site user, including administrators, if they knew a valid username on the site due to missing identity validation in the social login function social_login_using_email() of the plugin. This affects versions equal to, and less than, 5.0.1.7.

Frequently asked questions

What is CVE-2021-4073?: The RegistrationMagic WordPress plugin made it possible for unauthenticated users to log in as any site user, including administrators, if they knew a valid username on the site due to missing identity validation in the social login function social_login_using_email() of the plugin. This affects versions equal to, and less than, 5.0.1.7.
How severe is CVE-2021-4073?: CVE-2021-4073 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-2021-4073 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 7% (93rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-4073?: CVE-2021-4073 affects Metagauss Registrationmagic. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-4073?: 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-2021-4073 published?: CVE-2021-4073 was published on 2021-12-14 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:metagauss:registrationmagic:*:*:*:*:*:wordpress:*:*

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