Incorrect Authorization vulnerability in ash-project ash_graphql allows an authenticated subscriber in one tenant to receive another tenant's records over GraphQL subscriptions.
The subscription resolver in AshGraphql.Graphql.Resolver authorizes each notification payload in memory: its fast path calls Ash.can/3 with run_queries?: false, which evaluates the read policy filter against the in-memory record via Ash.Expr.eval/2 and never issues a query. Ash applies multitenancy at query-build and data-layer-prefix time, not inside query.filter, so the evaluated policy carries no tenant condition and a tenant-B notification routed to a tenant-A subscriber is emitted whenever the policy filter is true. The single-notification clause has no tenant guard at all, and the batched clause checks only the head of the notification list, so non-head entries authorize purely in memory. A tenant-scoped read is reached only when filter evaluation fails.
This issue affects ash_graphql: from 1.4.0 before 1.11.0.
{
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/80xxx/CVE-2026-80223.json",
"unresolved_ranges": [
{
"source": "AFFECTED_FIELD",
"extracted_events": [
{
"introduced": "4c377e541a2adb6befc651f3dccc6a797bc58ba9"
},
{
"fixed": "6e30b8b5a04bdeaed5d7514caa6b2d056d8d993e"
}
]
}
],
"cna_assigner": "EEF",
"cwe_ids": [
"CWE-863"
]
}