The Comments plugin (getgrav/grav-plugin-comments) for Grav CMS through version 1.2.10 registers an admin handler that returns comment data as JSON without any authentication check

Overview

The Comments plugin (getgrav/grav-plugin-comments) for Grav CMS through version 1.2.10 registers an admin handler that returns comment data as JSON without any authentication check. The handler branches on isAdmin(), which only indicates that the admin service is registered on the current route rather than that the visitor is authenticated, and it echoes the JSON and calls exit() during the plugins stage, before the classic Admin plugin would render its login screen. On a site using the classic Admin plugin with Comments enabled (the default), an unauthenticated remote attacker can request /admin/comments/page:<n> (e.g. page:0.001) and retrieve every comment from the last 7 days, including each commenter's email address and the absolute server filesystem path of the data file. Sites running the Grav 2.0 Admin Next stack (admin2 + api) are not affected via this path. The issue is fixed in 1.2.11, which requires an authenticated user with admin.comments or admin.super and removes the absolute filePath from the response.

Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.