{"id":"CVE-2026-82742","state":"PUBLISHED","title":"Ash.Filter.Runtime materializes a combinatorial cross-product over to-many relationships, exhausting memory","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.\n\nAsh.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.\n\nThis issue affects ash: from 1.29.0-rc0 before 3.32.2.","publishedAt":"2026-09-01T03:35:18.551Z","updatedAt":"2026-09-01T12:41:53.189Z","severity":{"score":5.9,"label":"Medium","version":"4.0","vector":"CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","source":"EEF"},"assigner":"EEF","products":["ash-project ash"],"affected":[{"vendor":"ash-project","product":"ash","packageName":"ash","packageURL":"pkg:hex/ash","defaultStatus":"unaffected","versions":[{"version":"1.29.0-rc0","status":"affected","lessThan":"3.32.2","versionType":"semver"}],"collectionURL":"https://repo.hex.pm","cpes":["cpe:2.3:a:ash-project:ash:*:*:*:*:*:*:*:*"],"modules":["'Elixir.Ash.Filter.Runtime'"],"programFiles":["lib/ash/filter/runtime.ex"],"programRoutines":[{"name":"'Elixir.Ash.Filter.Runtime':filter_matches/4"},{"name":"'Elixir.Ash.Filter.Runtime':flatten_relationships/2"}],"repo":"https://github.com/ash-project/ash"},{"vendor":"ash-project","product":"ash","packageName":"ash-project/ash","packageURL":"pkg:github/ash-project/ash","defaultStatus":"unaffected","versions":[{"version":"f6f5d194bfc7802bd32e48bf2eabd2d97a0109a4","status":"affected","lessThan":"da07f009e889819ec410fa1f0f12534bfb9e21dd","versionType":"git"}],"collectionURL":"https://github.com","cpes":["cpe:2.3:a:ash-project:ash:*:*:*:*:*:*:*:*"],"modules":["'Elixir.Ash.Filter.Runtime'"],"programFiles":["lib/ash/filter/runtime.ex"],"programRoutines":[{"name":"'Elixir.Ash.Filter.Runtime':filter_matches/4"},{"name":"'Elixir.Ash.Filter.Runtime':flatten_relationships/2"}],"repo":"https://github.com/ash-project/ash"}],"references":["https://github.com/ash-project/ash/security/advisories/GHSA-mgwj-c69v-6f83","https://cna.erlef.org/cves/CVE-2026-82742.html","https://osv.dev/vulnerability/EEF-CVE-2026-82742","https://github.com/ash-project/ash/commit/da07f009e889819ec410fa1f0f12534bfb9e21dd"],"weaknesses":["CWE-400"],"ingestedAt":"2026-10-29T20:13:15.269Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/82xxx/CVE-2026-82742.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-82742","state":"PUBLISHED","datePublished":"2026-09-01T03:35:18.551Z","dateUpdated":"2026-09-01T12:41:53.189Z","assignerShortName":"EEF","assignerOrgId":"6b3ad84c-e1a6-4bf7-a703-f496b71e49db","dateReserved":"2026-08-31T01:00:09.774Z"},"containers":{"cna":{"title":"Ash.Filter.Runtime materializes a combinatorial cross-product over to-many relationships, exhausting memory","descriptions":[{"lang":"en","value":"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.\n\nAsh.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.\n\nThis issue affects ash: from 1.29.0-rc0 before 3.32.2."}],"affected":[{"vendor":"ash-project","product":"ash","packageName":"ash","packageURL":"pkg:hex/ash","defaultStatus":"unaffected","versions":[{"version":"1.29.0-rc0","status":"affected","lessThan":"3.32.2","versionType":"semver"}],"collectionURL":"https://repo.hex.pm","cpes":["cpe:2.3:a:ash-project:ash:*:*:*:*:*:*:*:*"],"modules":["'Elixir.Ash.Filter.Runtime'"],"programFiles":["lib/ash/filter/runtime.ex"],"programRoutines":[{"name":"'Elixir.Ash.Filter.Runtime':filter_matches/4"},{"name":"'Elixir.Ash.Filter.Runtime':flatten_relationships/2"}],"repo":"https://github.com/ash-project/ash"},{"vendor":"ash-project","product":"ash","packageName":"ash-project/ash","packageURL":"pkg:github/ash-project/ash","defaultStatus":"unaffected","versions":[{"version":"f6f5d194bfc7802bd32e48bf2eabd2d97a0109a4","status":"affected","lessThan":"da07f009e889819ec410fa1f0f12534bfb9e21dd","versionType":"git"}],"collectionURL":"https://github.com","cpes":["cpe:2.3:a:ash-project:ash:*:*:*:*:*:*:*:*"],"modules":["'Elixir.Ash.Filter.Runtime'"],"programFiles":["lib/ash/filter/runtime.ex"],"programRoutines":[{"name":"'Elixir.Ash.Filter.Runtime':filter_matches/4"},{"name":"'Elixir.Ash.Filter.Runtime':flatten_relationships/2"}],"repo":"https://github.com/ash-project/ash"}],"references":[{"url":"https://github.com/ash-project/ash/security/advisories/GHSA-mgwj-c69v-6f83","tags":["vendor-advisory","related"]},{"url":"https://cna.erlef.org/cves/CVE-2026-82742.html","tags":["related"]},{"url":"https://osv.dev/vulnerability/EEF-CVE-2026-82742","tags":["related"]},{"url":"https://github.com/ash-project/ash/commit/da07f009e889819ec410fa1f0f12534bfb9e21dd","tags":["patch"]}],"metrics":[{"cvssV4_0":{"Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","Safety":"NOT_DEFINED","attackComplexity":"LOW","attackRequirements":"PRESENT","attackVector":"LOCAL","baseScore":5.9,"baseSeverity":"MEDIUM","privilegesRequired":"NONE","providerUrgency":"NOT_DEFINED","subAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","userInteraction":"NONE","valueDensity":"NOT_DEFINED","vectorString":"CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","version":"4.0","vulnAvailabilityImpact":"HIGH","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnerabilityResponseEffort":"NOT_DEFINED"},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-400","description":"CWE-400 Uncontrolled Resource Consumption","lang":"en","type":"CWE"}]}],"providerMetadata":{"shortName":"EEF","orgId":"6b3ad84c-e1a6-4bf7-a703-f496b71e49db","dateUpdated":"2026-09-01T03:35:18.551Z"},"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:a:ash-project:ash:*:*:*:*:*:*:*:*","versionEndExcluding":"3.32.2","versionStartIncluding":"1.29.0-rc0","vulnerable":true}],"negate":false,"operator":"OR"}],"operator":"AND"}],"credits":[{"lang":"en","type":"finder","value":"Peter Ullrich"},{"lang":"en","type":"remediation developer","value":"Zach Daniel / Ash Project"},{"lang":"en","type":"coordinator","value":"Jonatan Männchen / EEF"},{"lang":"en","type":"reporter","value":"Peter Ullrich"}],"impacts":[{"capecId":"CAPEC-130","descriptions":[{"lang":"en","value":"CAPEC-130 Excessive Allocation"}]}],"source":{"discovery":"EXTERNAL"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-09-01T12:41:35.557359Z","id":"CVE-2026-82742","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-09-01T12:41:53.189Z"}}]}}}