CVE-2021-4387: Opal Estate <= 1.6.11 - Cross-Site Request Forgery Bypass

Severity: high (CVSS 8.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2023-07-01 · updated 2026-06-17
Weakness: CWE-352

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.

Affected products

wpopal Opal Estate: through 1.6.11

References

https://blog.nintechnet.com/25-wordpress-plugins-vulnerable-to-csrf-attacks/
https://blog.nintechnet.com/more-wordpress-plugins-and-themes-vulnerable-to-csrf-attacks/
https://blog.nintechnet.com/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-1/
https://blog.nintechnet.com/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-2/
https://blog.nintechnet.com/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-3/
https://blog.nintechnet.com/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-4/
https://blog.nintechnet.com/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-5/
https://plugins.trac.wordpress.org/browser/opal-estate/trunk/inc/ajax-functions.php#L177
https://www.wordfence.com/threat-intel/vulnerabilities/id/2645899c-2b6b-48bd-8f33-2a837a951c5e?source=cve
https://blog.nintechnet.com/25-wordpress-plugins-vulnerable-to-csrf-attacks/
https://blog.nintechnet.com/more-wordpress-plugins-and-themes-vulnerable-to-csrf-attacks/
https://blog.nintechnet.com/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-1/

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