CVE Catalog

CVE-2026-81766

Low risk· EPSS 4%
Published: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.15%

4th percentile - higher than 4% of all known CVEs

Summary

The Really Simple Security WordPress plugin before 9.8.0 does not check if the user is allowed to install plugins, allowing a subsite administrator on a multisite network to install and execute arbitrary code in the network-shared plugin directory. Exploitation requires the network administrator to have enabled the plugin's administration menu for subsites, which is not the default.

Risk Assessment

Risk of full compromise of the WordPress multisite environment by a subsite administrator, potentially leading to arbitrary code execution in the network context.

Recommendation

Update the Really Simple Security plugin to version 9.8.0 or later. Additionally, if not necessary, disable the plugin's administration menu for subsites.

Related vulnerabilities

Original NVD description (English source)

The Really Simple Security WordPress plugin before 9.8.0 does not check that the user is allowed to install Really Simple Security WordPress plugin before 9.8.0 before installing one from a user-supplied URL, allowing an administrator of a subsite on a multisite network to install and execute arbitrary code in the network-shared Really Simple Security WordPress plugin before 9.8.0 directory, which WordPress otherwise reserves to the network administrator. Exploitation requires the network administrator to have enabled the Really Simple Security WordPress plugin before 9.8.0 administration menu for subsites, which is not the default.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS