CVE-2026-80223

Cross-tenant subscription disclosure in AshGraphql authorizes notifications in memory without a tenant-scoped read

Published Aug 30, 2026 CVSS 4.0 · 7.1 High EPSS < 1% KEV · Not listed
Description
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description 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.
Title Cross-tenant subscription disclosure in AshGraphql authorizes notifications in memory without a tenant-scoped read
First Time appeared Ash-project
Ash-project ash Graphql
Weaknesses CWE-863
CPEs cpe:2.3:a:ash-project:ash_graphql:*:*:*:*:*:*:*:*
Vendors & Products Ash-project
Ash-project ash Graphql
References
Metrics cvssV4_0

{'score': 7.1, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
EEF
Published
Updated
Aug 31, 2026, 3:58 PM
Reserved
Aug 30, 2026, 3:30 PM
Status
Deferred
Published
Aug 30, 2026, 7:17 PM
Modified
Sep 3, 2026, 5:15 AM