{"api_version":"1","generated_at":"2026-08-31T03:54:27+00:00","cve":"CVE-2026-81853","urls":{"html":"https://cve.report/CVE-2026-81853","api":"https://cve.report/api/cve/CVE-2026-81853.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-81853","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-81853"},"summary":{"title":"AshAdmin composite primary key decoding accepts arbitrary fields, enabling a secret-attribute oracle","description":"Authorization Bypass Through User-Controlled Key vulnerability in ash-project ash_admin turns a record-lookup URL into an equality oracle over sensitive attributes.\n\nAshAdmin.Helpers.decode_primary_key/2 decodes the composite-primary-key form (Base64 plus ETF) and returns the decoded map verbatim as the lookup filter, without checking that its keys are the resource's primary-key fields. The deserialization guards bound size, block new atoms and funs, and reject nested expressions, but none restricts which fields come back, and :safe still allows any already-interned attribute name. An attacker can therefore encode %{api_token: \"guess\"} and have it spliced into the lookup filter, brute-forcing a sensitive attribute value (API token, reset token) one equality guess at a time; Map.to_list/1 also accepts structs, yielding a bogus __struct__ key. The fix rejects any decoded key that is not a real primary-key field.\n\nThis issue affects ash_admin: from 0.1.0 before 1.3.1.","state":"PUBLISHED","assigner":"EEF","published_at":"2026-08-31 03:16:42","updated_at":"2026-08-31 03:16:42"},"problem_types":["CWE-639","CWE-639 CWE-639 Authorization Bypass Through User-Controlled 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Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-81853","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"ash-project","product":"ash_admin","version":"affected 0.1.0 1.3.1 semver","platforms":[]},{"source":"CNA","vendor":"ash-project","product":"ash_admin","version":"affected 98b03baa8422b94dd13e305bf08b8ee3f7232c7b 3c3e905d47f1155dcc1ca3fb347348b05a66065a git","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[{"source":"CNA","value":"Peter Ullrich","lang":"en"},{"source":"CNA","value":"Peter Ullrich","lang":"en"},{"source":"CNA","value":"Zach Daniel / Ash Project","lang":"en"},{"source":"CNA","value":"Jonatan Männchen / EEF","lang":"en"}],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"collectionURL":"https://repo.hex.pm","cpes":["cpe:2.3:a:ash-project:ash_admin:*:*:*:*:*:*:*:*"],"defaultStatus":"unaffected","modules":["'Elixir.AshAdmin.Helpers'"],"packageName":"ash_admin","packageURL":"pkg:hex/ash_admin","product":"ash_admin","programFiles":["lib/ash_admin/helpers.ex"],"programRoutines":[{"name":"'Elixir.AshAdmin.Helpers':decode_primary_key/2"}],"repo":"https://github.com/ash-project/ash_admin","vendor":"ash-project","versions":[{"lessThan":"1.3.1","status":"affected","version":"0.1.0","versionType":"semver"}]},{"collectionURL":"https://github.com","cpes":["cpe:2.3:a:ash-project:ash_admin:*:*:*:*:*:*:*:*"],"defaultStatus":"unaffected","modules":["'Elixir.AshAdmin.Helpers'"],"packageName":"ash-project/ash_admin","packageURL":"pkg:github/ash-project/ash_admin","product":"ash_admin","programFiles":["lib/ash_admin/helpers.ex"],"programRoutines":[{"name":"'Elixir.AshAdmin.Helpers':decode_primary_key/2"}],"repo":"https://github.com/ash-project/ash_admin","vendor":"ash-project","versions":[{"lessThan":"3c3e905d47f1155dcc1ca3fb347348b05a66065a","status":"affected","version":"98b03baa8422b94dd13e305bf08b8ee3f7232c7b","versionType":"git"}]}],"configurations":[{"lang":"en","supportingMedia":[{"base64":false,"type":"text/html","value":"<p>The resource has a composite primary key, and the deployment relies on AshAdmin's authorization (a custom actor plug and policies) so that reading otherwise-restricted attribute values crosses a boundary.</p>"},{"base64":false,"type":"text/markdown","value":"The resource has a composite primary key, and the deployment relies on AshAdmin's authorization (a custom actor plug and policies) so that reading otherwise-restricted attribute values crosses a boundary."}],"value":"The resource has a composite primary key, and the deployment relies on AshAdmin's authorization (a custom actor plug and policies) so that reading otherwise-restricted attribute values crosses a boundary."}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:a:ash-project:ash_admin:*:*:*:*:*:*:*:*","versionEndExcluding":"1.3.1","versionStartIncluding":"0.1.0","vulnerable":true}],"negate":false,"operator":"OR"}],"operator":"AND"}],"credits":[{"lang":"en","type":"finder","value":"Peter Ullrich"},{"lang":"en","type":"reporter","value":"Peter Ullrich"},{"lang":"en","type":"remediation developer","value":"Zach Daniel / Ash Project"},{"lang":"en","type":"coordinator","value":"Jonatan Männchen / EEF"}],"descriptions":[{"lang":"en","supportingMedia":[{"base64":false,"type":"text/html","value":"<p>Authorization Bypass Through User-Controlled Key vulnerability in ash-project ash_admin turns a record-lookup URL into an equality oracle over sensitive attributes.</p>\n<p><code>AshAdmin.Helpers.decode_primary_key/2</code> decodes the composite-primary-key form (Base64 plus ETF) and returns the decoded map verbatim as the lookup filter, without checking that its keys are the resource's primary-key fields. The deserialization guards bound size, block new atoms and funs, and reject nested expressions, but none restricts which fields come back, and <code>:safe</code> still allows any already-interned attribute name. An attacker can therefore encode <code>%{api_token: \"guess\"}</code> and have it spliced into the lookup filter, brute-forcing a sensitive attribute value (API token, reset token) one equality guess at a time; <code>Map.to_list/1</code> also accepts structs, yielding a bogus <code>__struct__</code> key. The fix rejects any decoded key that is not a real primary-key field.</p>\n<p>This issue affects ash_admin: from 0.1.0 before 1.3.1.</p>"},{"base64":false,"type":"text/markdown","value":"Authorization Bypass Through User-Controlled Key vulnerability in ash-project ash_admin turns a record-lookup URL into an equality oracle over sensitive attributes.\n\n`AshAdmin.Helpers.decode_primary_key/2` decodes the composite-primary-key form (Base64 plus ETF) and returns the decoded map verbatim as the lookup filter, without checking that its keys are the resource's primary-key fields. The deserialization guards bound size, block new atoms and funs, and reject nested expressions, but none restricts which fields come back, and `:safe` still allows any already-interned attribute name. An attacker can therefore encode `%{api_token: \"guess\"}` and have it spliced into the lookup filter, brute-forcing a sensitive attribute value (API token, reset token) one equality guess at a time; `Map.to_list/1` also accepts structs, yielding a bogus `__struct__` key. The fix rejects any decoded key that is not a real primary-key field.\n\nThis issue affects ash_admin: from 0.1.0 before 1.3.1."}],"value":"Authorization Bypass Through User-Controlled Key vulnerability in ash-project ash_admin turns a record-lookup URL into an equality oracle over sensitive attributes.\n\nAshAdmin.Helpers.decode_primary_key/2 decodes the composite-primary-key form (Base64 plus ETF) and returns the decoded map verbatim as the lookup filter, without checking that its keys are the resource's primary-key fields. The deserialization guards bound size, block new atoms and funs, and reject nested expressions, but none restricts which fields come back, and :safe still allows any already-interned attribute name. An attacker can therefore encode %{api_token: \"guess\"} and have it spliced into the lookup filter, brute-forcing a sensitive attribute value (API token, reset token) one equality guess at a time; Map.to_list/1 also accepts structs, yielding a bogus __struct__ key. The fix rejects any decoded key that is not a real primary-key field.\n\nThis issue affects ash_admin: from 0.1.0 before 1.3.1."}],"impacts":[{"capecId":"CAPEC-77","descriptions":[{"lang":"en","value":"CAPEC-77 Manipulating User-Controlled Variables"}]}],"metrics":[{"cvssV4_0":{"Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","Safety":"NOT_DEFINED","attackComplexity":"LOW","attackRequirements":"PRESENT","attackVector":"NETWORK","baseScore":2.3,"baseSeverity":"LOW","privilegesRequired":"LOW","providerUrgency":"NOT_DEFINED","subAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","userInteraction":"NONE","valueDensity":"NOT_DEFINED","vectorString":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N","version":"4.0","vulnAvailabilityImpact":"NONE","vulnConfidentialityImpact":"LOW","vulnIntegrityImpact":"NONE","vulnerabilityResponseEffort":"NOT_DEFINED"},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-639","description":"CWE-639 Authorization Bypass Through User-Controlled Key","lang":"en","type":"CWE"}]}],"providerMetadata":{"dateUpdated":"2026-08-31T02:31:29.547Z","orgId":"6b3ad84c-e1a6-4bf7-a703-f496b71e49db","shortName":"EEF"},"references":[{"tags":["vendor-advisory","related"],"url":"https://github.com/ash-project/ash_admin/security/advisories/GHSA-jxr8-hpv2-qp38"},{"tags":["related"],"url":"https://cna.erlef.org/cves/CVE-2026-81853.html"},{"tags":["related"],"url":"https://osv.dev/vulnerability/EEF-CVE-2026-81853"},{"tags":["patch"],"url":"https://github.com/ash-project/ash_admin/commit/3c3e905d47f1155dcc1ca3fb347348b05a66065a"}],"source":{"discovery":"EXTERNAL"},"title":"AshAdmin composite primary key decoding accepts arbitrary fields, enabling a secret-attribute oracle"}},"cveMetadata":{"assignerOrgId":"6b3ad84c-e1a6-4bf7-a703-f496b71e49db","assignerShortName":"EEF","cveId":"CVE-2026-81853","datePublished":"2026-08-31T02:31:29.547Z","dateReserved":"2026-08-30T23:15:02.371Z","dateUpdated":"2026-08-31T02:31:29.547Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-08-31 03:16:42","lastModifiedDate":"2026-08-31 03:16:42","problem_types":["CWE-639","CWE-639 CWE-639 Authorization Bypass Through User-Controlled Key"],"metrics":{"cvssMetricV40":[{"source":"6b3ad84c-e1a6-4bf7-a703-f496b71e49db","type":"Secondary","cvssData":{"version":"4.0","vectorString":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","baseScore":2.3,"baseSeverity":"LOW","attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"PRESENT","privilegesRequired":"LOW","userInteraction":"NONE","vulnConfidentialityImpact":"LOW","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","exploitMaturity":"NOT_DEFINED","confidentialityRequirement":"NOT_DEFINED","integrityRequirement":"NOT_DEFINED","availabilityRequirement":"NOT_DEFINED","modifiedAttackVector":"NOT_DEFINED","modifiedAttackComplexity":"NOT_DEFINED","modifiedAttackRequirements":"NOT_DEFINED","modifiedPrivilegesRequired":"NOT_DEFINED","modifiedUserInteraction":"NOT_DEFINED","modifiedVulnConfidentialityImpact":"NOT_DEFINED","modifiedVulnIntegrityImpact":"NOT_DEFINED","modifiedVulnAvailabilityImpact":"NOT_DEFINED","modifiedSubConfidentialityImpact":"NOT_DEFINED","modifiedSubIntegrityImpact":"NOT_DEFINED","modifiedSubAvailabilityImpact":"NOT_DEFINED","Safety":"NOT_DEFINED","Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","valueDensity":"NOT_DEFINED","vulnerabilityResponseEffort":"NOT_DEFINED","providerUrgency":"NOT_DEFINED"}}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"81853","Ordinal":"1","Title":"AshAdmin composite primary key decoding accepts arbitrary fields","CVE":"CVE-2026-81853","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"81853","Ordinal":"1","NoteData":"Authorization Bypass Through User-Controlled Key vulnerability in ash-project ash_admin turns a record-lookup URL into an equality oracle over sensitive attributes.\n\nAshAdmin.Helpers.decode_primary_key/2 decodes the composite-primary-key form (Base64 plus ETF) and returns the decoded map verbatim as the lookup filter, without checking that its keys are the resource's primary-key fields. The deserialization guards bound size, block new atoms and funs, and reject nested expressions, but none restricts which fields come back, and :safe still allows any already-interned attribute name. An attacker can therefore encode %{api_token: \"guess\"} and have it spliced into the lookup filter, brute-forcing a sensitive attribute value (API token, reset token) one equality guess at a time; Map.to_list/1 also accepts structs, yielding a bogus __struct__ key. The fix rejects any decoded key that is not a real primary-key field.\n\nThis issue affects ash_admin: from 0.1.0 before 1.3.1.","Type":"Description","Title":"AshAdmin composite primary key decoding accepts arbitrary fields"}]}}}