#ResPublicae has been upgraded to Mastodon v3.5.9, a security release.
https://github.com/mastodon/mastodon/releases?q=v3.5&expanded=true

The upgrade was painless. Thank you #MastoDev and especially @Claire[@]sitedethib.com for offering backports to pre-v4 releases and for the clear instructions.

While the details of CVE-2023-36459 have not been published yet, the title suggests the vulnerability may be exploitable even on an instance like ours where no third party can directly post anything.
https://github.com/mastodon/mastodon/releases?q=v3.5&expanded=true