CVE-2026-115635

AshPostgres returns another tenant's record for a skipped upsert when return_skipped_upsert? is set

Published Oct 25, 2026 CVSS 4.0 · 6 Medium EPSS < 1% KEV · Not listed
Description
Incorrect Authorization vulnerability in ash-project ash_postgres allows a user to read another tenant's record through a skipped upsert.

When Ash.bulk_create/4 or a single create runs as an upsert with return_skipped_upsert?: true and the upsert is skipped (for example because its upsert_condition does not hold), AshPostgres.DataLayer reads the existing row back by the upsert identity in do_bulk_create/3 and upsert/4. That lookup did not apply the resource's attribute multitenancy, so on a resource using strategy :attribute it could match and return the row of another tenant with the same identity values, exposing its fields to the caller.

This issue affects ash_postgres: from 2.6.22 before 2.15.2.

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': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description Incorrect Authorization vulnerability in ash-project ash_postgres allows a user to read another tenant's record through a skipped upsert. When Ash.bulk_create/4 or a single create runs as an upsert with return_skipped_upsert?: true and the upsert is skipped (for example because its upsert_condition does not hold), AshPostgres.DataLayer reads the existing row back by the upsert identity in do_bulk_create/3 and upsert/4. That lookup did not apply the resource's attribute multitenancy, so on a resource using strategy :attribute it could match and return the row of another tenant with the same identity values, exposing its fields to the caller. This issue affects ash_postgres: from 2.6.22 before 2.15.2.
Title AshPostgres returns another tenant's record for a skipped upsert when return_skipped_upsert? is set
First Time appeared Ash-project
Ash-project ash Postgres
Weaknesses CWE-863
CPEs cpe:2.3:a:ash-project:ash_postgres:*:*:*:*:*:*:*:*
Vendors & Products Ash-project
Ash-project ash Postgres
References
Metrics cvssV4_0

{'score': 6, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
EEF
Published
Updated
Oct 26, 2026, 2:35 PM
Reserved
Oct 23, 2026, 1:00 PM
Status
Deferred
Published
Oct 25, 2026, 8:16 PM
Modified
Oct 26, 2026, 3:16 PM