CVE-2026-81766

Really Simple Security < 9.8.0 - Multisite Subsite Admin+ Arbitrary Plugin Installation via rsp_upgrade_install_plugin

Published Aug 30, 2026 CVSS 3.1 · 6.6 Medium EPSS < 1% KEV · Not listed
Description
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
First Time appeared Really-simple-plugins
Really-simple-plugins really Simple Security
Wordpress
Wordpress wordpress
Vendors & Products Really-simple-plugins
Really-simple-plugins really Simple Security
Wordpress
Wordpress wordpress
Type Values Removed Values Added
Weaknesses CWE-284
CWE-285
Type Values Removed Values Added
Weaknesses CWE-269
Metrics cvssV3_1

{'score': 6.6, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H'}

ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
Weaknesses CWE-284
CWE-285
Type Values Removed Values Added
Description 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.
Title Really Simple Security < 9.8.0 - Multisite Subsite Admin+ Arbitrary Plugin Installation via rsp_upgrade_install_plugin
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
WPScan
Published
Updated
Aug 31, 2026, 12:38 PM
Reserved
Aug 27, 2026, 12:23 PM
Status
Deferred
Published
Aug 30, 2026, 7:17 AM
Modified
Aug 31, 2026, 8:14 PM