CVE-2026-77454exists/2 predicate silently dropped on limited relationships with a parent() filter in AshSql

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.

CVSS

5.9 MEDIUM (v4.0, CNA)CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N

Weakness (CWE)

CWE-863

Known exploited

Not in CISA's KEV catalog

EPSS (exploitation in the next 30 days)

Not loaded for this CVE

Assigned by

EEF

NVD analysis

Deferred

Record last updated

Aug 31, 2026

First seen by InfoSec Signals

Oct 9, 2026

The CVE record on cve.org · NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.