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.
Metrics
CVSS 4.0 6.0/10
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:XWeakness enumeration
Affected software
| Vendor | Product | Versions |
|---|---|---|
| ash-project | ash_postgres | >= 2.6.22, < 2.15.2 |
| ash-project | ash_postgres | >= af0903f1380468bbe1b61fe65acb33772b5e24a5, < 8aa81220c401cae412d21078d11b3519ea25d3a9 |
References
- https://cna.erlef.org/cves/CVE-2026-115635.html
- https://github.com/ash-project/ash/security/advisories/GHSA-36hg-wwp2-fg8w
- https://github.com/ash-project/ash_postgres/commit/8aa81220c401cae412d21078d11b3519ea25d3a9
- https://github.com/ash-project/ash_postgres/commit/af0903f1380468bbe1b61fe65acb33772b5e24a5
- https://osv.dev/vulnerability/EEF-CVE-2026-115635
Timeline
- Published
- Oct 25, 2026
- Last modified
- Oct 26, 2026
- NVD status
- Deferred