published August 30, 2026
Allocation of Resources Without Limits or Throttling vulnerability in ash-project ash_graphql allows an unauthenticated client to bypass the configured GraphQL query-complexity limit and force an unbounded database read.
AshGraphql.Graphql.Resolver.query_complexity/3 multiplies child complexity by the requested page size only when the argument map contains :limit (offset pagination). Relay connections and keyset pagination use first and last, which never match that clause and fall through to the catch-all that returns child_complexity + 1. A nested relay query such as posts(first: 500) { edges { node { comments(first: 500) { ... } } } } therefore scores as trivially cheap while materializing the full fan-out, passing an Absinthe max_complexity cap that rejects the equivalent limit-based query. The fix adds first and last clauses clamped to the action's page size.
This issue affects ash_graphql: from 0.16.23 before 1.11.0.