The Post Grid Gutenberg Blocks and WordPress Blog Plugin WordPress plugin before 4.1.0 does not validate and escape some of its block options before outputting them back in a page/post where the block is embed, which could allow users with the contributor role and above to perform Stored Cross-Site Scripting attacks
https://wpscan.com/vulnerability/635be98d-4c17-4e75-871f-9794d85a2eb1/