CVE-2026-81766
Really Simple Security < 9.8.0 - Multisite Subsite Admin+ Arbitrary Plugin Installation via rsp_upgrade_install_plugin
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
- Really Simple Security
- CVSS v3.1 CNA
- 6.6 MEDIUM
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H - EPSS
- 0.43% chance of exploitation in the next 30 days, 36th percentile
- Published
- 2026-08-30
- Updated
- 2026-08-31