Appsmith is a platform to build admin panels, internal tools, and dashboards. Users invited as "App Viewer" should not have access to development information of a workspace. Datasources are such a component in a workspace. Yet, in versions of Appsmith prior to 1.51, app viewers are able to get a list of datasources in a workspace they're a member of. This information disclosure does NOT expose sensitive data in the datasources, such as database passwords and API Keys. The attacker needs to have been invited to a workspace as a "viewer", by someone in that workspace with access to invite. The attacker then needs to be able to signup/login to that Appsmith instance. The issue is patched in version 1.51. No known workarounds are available.
Appsmith's Broken Access Control Allows Viewer Role User to Query Datasources