grist-core is a spreadsheet hosting server. A user visiting a malicious document and clicking on a link in a HyperLink cell using a control modifier (meaning for example Ctrl+click) could have their account compromised, since the link could use the javascript: scheme and be evaluated in the context of their current page. This issue has been patched in version 1.3.2. Users are advised to upgrade. Users unable to upgrade should avoid clicking on HyperLink cell links using a control modifier in documents prepared by people they do not trust.