Vulnerability · Published Aug 30, 2026 · Assigned by WPScan

CVE-2026-81766Really Simple Security < 9.8.0 - Multisite Subsite Admin+ Arbitrary Plugin Installation via rsp_upgrade_install_plugin

Medium 6.6

In plain English

A medium-severity privilege mismanagement in Really Simple Security from Unknown. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 38% of all known vulnerabilities).

Severity (CVSS 3.1)6.6Medium

Exploit odds (30 days)0.4%top 62.0% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official 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.

Affected products (as reported)

Vendor	Product	Versions
Unknown	Really Simple Security	0 – before 9.8.0

Weakness: CWE-269 · Vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H

References

https://wpscan.com/vulnerability/948d70a2-605e-4a83-8feb-eca4dbb5f948/ exploit, vdb-entry, technical-description