{"id":"CVE-2026-82744","state":"PUBLISHED","title":"Ash.Reactor change step fails open, skipping a change when its where guard raises","description":"Not Failing Securely (Failing Open) vulnerability in ash-project ash skips an Ash.Reactor change when the guard controlling it raises, so a change meant to run does not.\n\nAn Ash.Reactor change step can be gated by where validations that decide whether the change runs. Ash.Reactor.ChangeStep (lib/ash/reactor/steps/change_step.ex) evaluated those guards in apply_where_clauses/3, and apply_validation rescued any exception into {:error, error}. The reduce treated that identically to a guard whose condition was simply not met and bypassed the change. So when a guard raises (for example on attacker-influenced input), a change that enforces a security-relevant modification is skipped rather than failing the step. The fix distinguishes a raised exception (now {:raised, error}) and halts the step with an error, failing closed.\n\nThis issue affects ash: from 3.0.0-rc.17 before 3.32.2.","publishedAt":"2026-09-01T03:39:42.668Z","updatedAt":"2026-09-01T15:15:56.042Z","severity":{"score":2.1,"label":"Low","version":"4.0","vector":"CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/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":"3.0.0-rc.17","status":"affected","lessThan":"3.32.2","versionType":"semver"}],"collectionURL":"https://repo.hex.pm","cpes":["cpe:2.3:a:ash-project:ash:*:*:*:*:*:*:*:*"],"modules":["'Elixir.Ash.Reactor.ChangeStep'"],"programFiles":["lib/ash/reactor/steps/change_step.ex"],"programRoutines":[{"name":"'Elixir.Ash.Reactor.ChangeStep':apply_where_clauses/3"}],"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":"321f43bd05ad9544e693cbf797243693e51a6be4","status":"affected","lessThan":"6d2eb86ea8d2ba5ffac89c1b8b9bf46e331feabc","versionType":"git"}],"collectionURL":"https://github.com","cpes":["cpe:2.3:a:ash-project:ash:*:*:*:*:*:*:*:*"],"modules":["'Elixir.Ash.Reactor.ChangeStep'"],"programFiles":["lib/ash/reactor/steps/change_step.ex"],"programRoutines":[{"name":"'Elixir.Ash.Reactor.ChangeStep':apply_where_clauses/3"}],"repo":"https://github.com/ash-project/ash"}],"references":["https://github.com/ash-project/ash/security/advisories/GHSA-3xq4-m876-fr88","https://cna.erlef.org/cves/CVE-2026-82744.html","https://osv.dev/vulnerability/EEF-CVE-2026-82744","https://github.com/ash-project/ash/commit/6d2eb86ea8d2ba5ffac89c1b8b9bf46e331feabc"],"weaknesses":["CWE-636"],"ingestedAt":"2026-10-29T20:13:15.269Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/82xxx/CVE-2026-82744.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-82744","state":"PUBLISHED","datePublished":"2026-09-01T03:39:42.668Z","dateUpdated":"2026-09-01T15:15:56.042Z","assignerShortName":"EEF","assignerOrgId":"6b3ad84c-e1a6-4bf7-a703-f496b71e49db","dateReserved":"2026-08-31T01:00:09.774Z"},"containers":{"cna":{"title":"Ash.Reactor change step fails open, skipping a change when its where guard raises","descriptions":[{"lang":"en","value":"Not Failing Securely (Failing Open) vulnerability in ash-project ash skips an Ash.Reactor change when the guard controlling it raises, so a change meant to run does not.\n\nAn Ash.Reactor change step can be gated by where validations that decide whether the change runs. Ash.Reactor.ChangeStep (lib/ash/reactor/steps/change_step.ex) evaluated those guards in apply_where_clauses/3, and apply_validation rescued any exception into {:error, error}. The reduce treated that identically to a guard whose condition was simply not met and bypassed the change. So when a guard raises (for example on attacker-influenced input), a change that enforces a security-relevant modification is skipped rather than failing the step. The fix distinguishes a raised exception (now {:raised, error}) and halts the step with an error, failing closed.\n\nThis issue affects ash: from 3.0.0-rc.17 before 3.32.2."}],"affected":[{"vendor":"ash-project","product":"ash","packageName":"ash","packageURL":"pkg:hex/ash","defaultStatus":"unaffected","versions":[{"version":"3.0.0-rc.17","status":"affected","lessThan":"3.32.2","versionType":"semver"}],"collectionURL":"https://repo.hex.pm","cpes":["cpe:2.3:a:ash-project:ash:*:*:*:*:*:*:*:*"],"modules":["'Elixir.Ash.Reactor.ChangeStep'"],"programFiles":["lib/ash/reactor/steps/change_step.ex"],"programRoutines":[{"name":"'Elixir.Ash.Reactor.ChangeStep':apply_where_clauses/3"}],"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":"321f43bd05ad9544e693cbf797243693e51a6be4","status":"affected","lessThan":"6d2eb86ea8d2ba5ffac89c1b8b9bf46e331feabc","versionType":"git"}],"collectionURL":"https://github.com","cpes":["cpe:2.3:a:ash-project:ash:*:*:*:*:*:*:*:*"],"modules":["'Elixir.Ash.Reactor.ChangeStep'"],"programFiles":["lib/ash/reactor/steps/change_step.ex"],"programRoutines":[{"name":"'Elixir.Ash.Reactor.ChangeStep':apply_where_clauses/3"}],"repo":"https://github.com/ash-project/ash"}],"references":[{"url":"https://github.com/ash-project/ash/security/advisories/GHSA-3xq4-m876-fr88","tags":["vendor-advisory","related"]},{"url":"https://cna.erlef.org/cves/CVE-2026-82744.html","tags":["related"]},{"url":"https://osv.dev/vulnerability/EEF-CVE-2026-82744","tags":["related"]},{"url":"https://github.com/ash-project/ash/commit/6d2eb86ea8d2ba5ffac89c1b8b9bf46e331feabc","tags":["patch"]}],"metrics":[{"cvssV4_0":{"Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","Safety":"NOT_DEFINED","attackComplexity":"LOW","attackRequirements":"PRESENT","attackVector":"LOCAL","baseScore":2.1,"baseSeverity":"LOW","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:L/VA:N/SC:N/SI:N/SA:N","version":"4.0","vulnAvailabilityImpact":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"LOW","vulnerabilityResponseEffort":"NOT_DEFINED"},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-636","description":"CWE-636 Not Failing Securely ('Failing Open')","lang":"en","type":"CWE"}]}],"providerMetadata":{"shortName":"EEF","orgId":"6b3ad84c-e1a6-4bf7-a703-f496b71e49db","dateUpdated":"2026-09-01T03:39:42.668Z"},"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:a:ash-project:ash:*:*:*:*:*:*:*:*","versionEndExcluding":"3.32.2","versionStartIncluding":"3.0.0-rc.17","vulnerable":true}],"negate":false,"operator":"OR"}],"operator":"AND"}],"credits":[{"lang":"en","type":"finder","value":"Peter Ullrich"},{"lang":"en","type":"coordinator","value":"Jonatan Männchen / EEF"},{"lang":"en","type":"remediation developer","value":"Zach Daniel / Ash Project"},{"lang":"en","type":"reporter","value":"Peter Ullrich"}],"impacts":[{"capecId":"CAPEC-153","descriptions":[{"lang":"en","value":"CAPEC-153 Input Data Manipulation"}]}],"source":{"discovery":"EXTERNAL"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/ash-project/ash/security/advisories/GHSA-3xq4-m876-fr88","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-09-01T15:15:37.062501Z","id":"CVE-2026-82744","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-09-01T15:15:56.042Z"}}]}}}