How severe is CVE-2021-4387?

CVE-2021-4387 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2021-4387 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (43rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-4387?

CVE-2021-4387 affects Wpopal Opal Estate. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-4387?

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

When was CVE-2021-4387 published?

CVE-2021-4387 was published on 2023-07-01 and last updated on 2026-06-17.

CVE-2021-4387

CVE-2021-4387 is a medium-severity vulnerability in Wpopal Opal Estate with a CVSS 3.x base score of 4.3. 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-352.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
EPSS exploit prediction: 1% (43rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-352
Affected product: Wpopal Opal Estate
Published: 2023-07-01
Last modified: 2026-06-17

Description

The Opal Estate plugin for WordPress is vulnerable to Cross-Site Request Forgery in versions up to, and including, 1.6.11. This is due to missing or incorrect nonce validation on the opalestate_set_feature_property() and opalestate_remove_feature_property() functions. This makes it possible for unauthenticated attackers to set and remove featured properties via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.

Frequently asked questions

What is CVE-2021-4387?: The Opal Estate plugin for WordPress is vulnerable to Cross-Site Request Forgery in versions up to, and including, 1.6.11. This is due to missing or incorrect nonce validation on the opalestate_set_feature_property() and opalestate_remove_feature_property() functions. This makes it possible for unauthenticated attackers to set and remove featured properties via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.
How severe is CVE-2021-4387?: CVE-2021-4387 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2021-4387 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (43rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-4387?: CVE-2021-4387 affects Wpopal Opal Estate. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-4387?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-4387 published?: CVE-2021-4387 was published on 2023-07-01 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:wpopal:opal_estate:*:*:*:*:*:wordpress:*:*

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