{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-81853",
        "assignerOrgId": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
        "state": "PUBLISHED",
        "assignerShortName": "EEF",
        "dateReserved": "2026-08-30T23:15:02.371Z",
        "datePublished": "2026-08-31T02:31:29.547Z",
        "dateUpdated": "2026-08-31T15:58:40.226Z"
    },
    "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": {
                "orgId": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
                "shortName": "EEF",
                "dateUpdated": "2026-08-31T02:31:29.547Z"
            },
            "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"
        },
        "adp": [
            {
                "references": [
                    {
                        "url": "https://github.com/ash-project/ash_admin/security/advisories/GHSA-jxr8-hpv2-qp38",
                        "tags": [
                            "exploit"
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                    }
                ],
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-08-31T15:57:41.689629Z",
                                "id": "CVE-2026-81853",
                                "options": [
                                    {
                                        "Exploitation": "poc"
                                    },
                                    {
                                        "Automatable": "no"
                                    },
                                    {
                                        "Technical Impact": "partial"
                                    }
                                ],
                                "role": "CISA Coordinator",
                                "version": "2.0.3"
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                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
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                    "dateUpdated": "2026-08-31T15:58:40.226Z"
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}