High severity · published Aug 30, 2026
CVE-2026-78699
rename_tenant returns :ok on a failed rename, enabling cross-tenant access in AshPostgres
7.2
CVSS
0.2%
EPSS
No
On KEV
Description
Unchecked Return Value vulnerability in ash-project ash_postgres allows a user who can drive a tenant rename to a name that collides with an existing tenant's schema to have their tenant record repointed at that other tenant's live schema, gaining access to its data. AshPostgres.MultiTenancy.rename_tenant/3 issues the ALTER SCHEMA ... RENAME TO ... with the non-raising Ecto.Adapters.SQL.query/2, discards its {:ok, _} | {:error, _} result, and unconditionally returns :ok. PostgreSQL rejects the rename when the target schema already exists (and on insufficient privilege or lock timeout), but that failure never reaches the caller. The calling manage_tenant update action therefore sees success and commits the tenant row with the new name, which is the schema of a different existing tenant, so subsequent reads and writes for that tenant run against the other tenant's data. This issue affects ash_postgres: from 0.25.0 before 2.13.0.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 5% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AS
ash_postgres · ash-project
0.25.0 before 2.13.0; 03510dae24020e302558ef947be7ea874a9ce756 before 8544ab15fe45784553c2d2da8ee1a388eee0174b · source: vendor
Affected product
AS
ash_postgres
ash-project
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