The Speed Optimizer WordPress plugin before 7.8.5 does not sanitise or escape some of its settings before outputting them in the head of front-end pages, which could allow high-privilege users such as admins to perform Stored Cross-Site Scripting attacks even when the unfilteredhtml capability is disallowed (for example in a multisite setup).
The Speed Optimizer WordPress plugin before 7.8.5 does not verify network-level privilege before applying an option change to the whole multisite network, nor restrict which option may be changed, allowing a site administrator who is not a Super Admin to create or overwrite network-wide options.
Missing Authorization vulnerability in SiteGround Speed Optimizer.This issue affects Speed Optimizer: from n/a through 7.4.6.