Impact

An attacker with master key access can execute arbitrary SQL statements on the PostgreSQL database by injecting SQL metacharacters into field name parameters of the aggregate $group pipeline stage or the distinct operation. This allows privilege escalation from Parse Server application-level administrator to PostgreSQL database-level access.

Only Parse Server deployments using PostgreSQL are affected. MongoDB deployments are not affected.

Patches

Field names in the aggregate $group.id object values and distinct dot-notation parameters are now validated to only contain alphanumeric characters and underscores, preventing SQL injection via the :raw interpolation used in the PostgreSQL storage adapter.

Workarounds

No workaround. Upgrade to a patched version.