Medium severity · published Oct 25, 2026
CVE-2026-115627
AshPostgres ignores attribute multitenancy on the join resource when loading many_to_many and through relationships, returning records related through other tenants' rows
New
6.0
CVSS
0.2%
EPSS
No
On KEV
Description
Incorrect Authorization vulnerability in ash-project ash_postgres allows a user to load destination records linked to a source record only through another tenant's join rows.
When a many_to_many relationship, or a through relationship, is loaded with a lateral join (for example with a per-record limit or sort), AshPostgres.DataLayer builds the query for the join resource, and for each resource along a through path, in lateral_join_query/3 and through_step_queries/4 without running that resource's read action, which is where attribute multitenancy is applied. When those resources use strategy :attribute multitenancy, rows belonging to other tenants were joined, so the load returned destination records that the caller's tenant is not related to.
This issue affects ash_postgres: from 0.38.0 before 2.15.2.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 16% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AS
ash_postgres · ash-project
0.38.0 before 2.15.2; 7115bec58678f13b1ac2fb4822a0ba1aea9dbec5 before 8c25c945c39a45299193fe70b09fc2fa2aacac7b · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-115627
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-115627
cna.erlef.org
https://cna.erlef.org/cves/CVE-2026-115627.html
github.com
https://github.com/ash-project/ash/security/advisories/GHSA-gr2r-f49c-9gm2
github.com
https://github.com/ash-project/ash_postgres/commit/7115bec58678f13b1ac2fb4822a0ba1aea9dbec5
github.com
https://github.com/ash-project/ash_postgres/commit/8c25c945c39a45299193fe70b09fc2fa2aacac7b
osv.dev
https://osv.dev/vulnerability/EEF-CVE-2026-115627
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