Medium severity · published Sep 1, 2026
CVE-2026-82742
Ash.Filter.Runtime materializes a combinatorial cross-product over to-many relationships, exhausting memory
5.9
CVSS
0.2%
EPSS
No
On KEV
Description
Uncontrolled Resource Consumption vulnerability in ash-project ash lets an attacker exhaust node memory by matching a filter that spans multiple to-many relationships in memory.
Ash.Filter.Runtime matches a filter against an in-memory record by first expanding the record into combinations of its related rows. flatten_relationships/2 (lib/ash/filter/runtime.ex) eagerly built the full Cartesian product across the filter's to-many relationship paths, so a record with K to-many relationships of M rows each materialized on the order of M^K scenarios before any predicate was checked. A filter or dataset that reaches several sizeable to-many relationships therefore allocates memory combinatorially and can exhaust the node. The fix streams the expansion lazily and short-circuits on the first matching scenario, bounding the work.
This issue affects ash: from 1.29.0-rc0 before 3.32.2.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 8% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AS
ash · ash-project
1.29.0-rc0 before 3.32.2; f6f5d194bfc7802bd32e48bf2eabd2d97a0109a4 before da07f009e889819ec410fa1f0f12534bfb9e21dd · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-82742
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-82742
cna.erlef.org
https://cna.erlef.org/cves/CVE-2026-82742.html
github.com
https://github.com/ash-project/ash/commit/da07f009e889819ec410fa1f0f12534bfb9e21dd
github.com
https://github.com/ash-project/ash/security/advisories/GHSA-mgwj-c69v-6f83
osv.dev
https://osv.dev/vulnerability/EEF-CVE-2026-82742
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