CVE-2026-78699

rename_tenant returns :ok on a failed rename, enabling cross-tenant access in AshPostgres

HIGH
7.2
CVSS Score
Published: August 30, 2026 at 03:13 PM UTC
Updated: September 1, 2026 at 09:31 PM UTC
1 product affected across 1 vendorAshPostgres

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Severity
HIGH7.2
Exploit prediction
EPSS 0.2%
SSVC
PoC

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

0.25.0 ≤ v < 2.13.00.25.03510dae24020e302558ef947be7ea874a9ce756
Vendor states this is fixed in 8544ab15fe45784553c2d2da8ee1a388eee0174b (fixed)
Affected range stops below 2.13.0, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCPoCNot automatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.2HIGHEEF
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-252

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