EEF-CVE-2026-77454

## Summary

Incorrect Authorization vulnerability in ash-project ash\_sql allows a caller to bypass a scoping or authorization filter expressed as exists/2 over a relationship that declares both a limit (or from\_many?) and a parent(...)-referencing filter or sort.

AshSql.Join.related\_query/3 skips the caller-supplied exists predicate for such relationships and delegates it to limit\_from\_many/5. When the relationship's own filter or sort references parent(...), limit\_from\_many/5 takes a branch that drops both the limit and the predicate, emitting a bare correlated EXISTS with no predicate. The check then matches any record that has any related row. Most severely, when the expression backs a policy (for example authorize\_if expr(exists(memberships, user\_id == ^actor(:id)))), the actor-scoping condition disappears and the policy passes for any actor with any related row.

This issue affects ash\_sql: from 0.4.1 before 0.7.1.

## Configuration

An application must use exists/2 (in a filter or a policy) over a relationship that declares both a limit or from\_many? and a filter or sort that references parent(...). The predicate supplied to exists/2 is the one that is dropped.