{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-94201",
        "assignerOrgId": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
        "state": "PUBLISHED",
        "assignerShortName": "EEF",
        "dateReserved": "2026-09-24T09:15:02.216Z",
        "datePublished": "2026-10-05T19:19:51.326Z",
        "dateUpdated": "2026-10-06T13:41:22.142Z"
    },
    "containers": {
        "cna": {
            "affected": [
                {
                    "collectionURL": "https://repo.hex.pm",
                    "cpes": [
                        "cpe:2.3:a:ash-project:ash:*:*:*:*:*:*:*:*"
                    ],
                    "defaultStatus": "unaffected",
                    "modules": [
                        "'Elixir.Ash.Type.Atom'"
                    ],
                    "packageName": "ash",
                    "packageURL": "pkg:hex/ash",
                    "product": "ash",
                    "programFiles": [
                        "lib/ash/type/atom.ex"
                    ],
                    "programRoutines": [
                        {
                            "name": "'Elixir.Ash.Type.Atom':cast_value/2"
                        }
                    ],
                    "repo": "https://github.com/ash-project/ash",
                    "vendor": "ash-project",
                    "versions": [
                        {
                            "lessThan": "3.34.3",
                            "status": "affected",
                            "version": "3.5.1",
                            "versionType": "semver"
                        }
                    ]
                },
                {
                    "collectionURL": "https://github.com",
                    "cpes": [
                        "cpe:2.3:a:ash-project:ash:*:*:*:*:*:*:*:*"
                    ],
                    "defaultStatus": "unaffected",
                    "modules": [
                        "'Elixir.Ash.Type.Atom'"
                    ],
                    "packageName": "ash-project/ash",
                    "packageURL": "pkg:github/ash-project/ash",
                    "product": "ash",
                    "programFiles": [
                        "lib/ash/type/atom.ex"
                    ],
                    "programRoutines": [
                        {
                            "name": "'Elixir.Ash.Type.Atom':cast_value/2"
                        }
                    ],
                    "repo": "https://github.com/ash-project/ash",
                    "vendor": "ash-project",
                    "versions": [
                        {
                            "lessThan": "5282f3f513053628cdd1bf2236ea22d975d934d4",
                            "status": "affected",
                            "version": "2970ba3bd5d36d6ad04c731ac87385375d457147",
                            "versionType": "git"
                        }
                    ]
                }
            ],
            "configurations": [
                {
                    "lang": "en",
                    "supportingMedia": [
                        {
                            "base64": false,
                            "type": "text/html",
                            "value": "<p>Reachable only when an application exposes a public, filterable <code>:atom</code> attribute declared with the <code>unsafe_to_atom?: true</code> constraint, and an actor can supply filter values for it (for example through AshGraphql, AshJsonApi, or <code>Ash.Query.filter_input/2</code>). AshPaperTrail's version resources ship such an attribute (<code>version_action_name</code>) by default.</p>"
                        },
                        {
                            "base64": false,
                            "type": "text/markdown",
                            "value": "Reachable only when an application exposes a public, filterable `:atom` attribute declared with the `unsafe_to_atom?: true` constraint, and an actor can supply filter values for it (for example through AshGraphql, AshJsonApi, or `Ash.Query.filter_input/2`). AshPaperTrail's version resources ship such an attribute (`version_action_name`) by default."
                        }
                    ],
                    "value": "Reachable only when an application exposes a public, filterable :atom attribute declared with the unsafe_to_atom?: true constraint, and an actor can supply filter values for it (for example through AshGraphql, AshJsonApi, or Ash.Query.filter_input/2). AshPaperTrail's version resources ship such an attribute (version_action_name) by default."
                }
            ],
            "cpeApplicability": [
                {
                    "nodes": [
                        {
                            "cpeMatch": [
                                {
                                    "criteria": "cpe:2.3:a:ash-project:ash:*:*:*:*:*:*:*:*",
                                    "versionEndExcluding": "3.34.3",
                                    "versionStartIncluding": "3.5.1",
                                    "vulnerable": true
                                }
                            ],
                            "negate": false,
                            "operator": "OR"
                        }
                    ],
                    "operator": "AND"
                }
            ],
            "credits": [
                {
                    "lang": "en",
                    "type": "finder",
                    "value": "Quinn Wilton"
                },
                {
                    "lang": "en",
                    "type": "reporter",
                    "value": "Quinn Wilton"
                },
                {
                    "lang": "en",
                    "type": "remediation developer",
                    "value": "Zach Daniel / Ash Project"
                },
                {
                    "lang": "en",
                    "type": "coordinator",
                    "value": "Jonatan Männchen / EEF"
                }
            ],
            "dateAssigned": "2026-10-04T15:49:18.000Z",
            "descriptions": [
                {
                    "lang": "en",
                    "supportingMedia": [
                        {
                            "base64": false,
                            "type": "text/html",
                            "value": "<p>Ash stores <code>:atom</code>-typed attributes as strings and compares them as strings. When such an attribute is referenced in a filter, the comparison value is coerced through <code>Ash.Type.Atom</code>. Because the type defined no <code>coerce/2</code> callback, coercion fell back to the default (<code>cast_input/2</code>), which calls <code>String.to_atom/1</code> when the attribute is configured with the <code>unsafe_to_atom?: true</code> constraint.</p>\n<p>Filtering such an attribute with attacker-controlled strings therefore interned a new, permanent atom for every distinct value. Atoms are never garbage collected and the BEAM caps the atom table, so an actor who can supply filter values for a public, filterable <code>:atom</code> attribute declared with <code>unsafe_to_atom?: true</code> can exhaust the atom table and crash the node (denial of service). AshPaperTrail is a notable example: its version resources expose a public, filterable <code>version_action_name</code> atom attribute with <code>unsafe_to_atom?: true</code> by default.</p>\n<p>The fix adds a <code>coerce/2</code> to <code>Ash.Type.Atom</code> that never interns atoms — a comparison value is left as a string, since the type is stored and compared as a string. Setting the attribute from action input (<code>cast_input/2</code>, which still honors <code>unsafe_to_atom?</code>) is unchanged.</p>\n<p>This issue affects ash: from 3.5.1 before 3.34.3.</p>"
                        },
                        {
                            "base64": false,
                            "type": "text/markdown",
                            "value": "Ash stores `:atom`-typed attributes as strings and compares them as strings. When such an attribute is referenced in a filter, the comparison value is coerced through `Ash.Type.Atom`. Because the type defined no `coerce/2` callback, coercion fell back to the default (`cast_input/2`), which calls `String.to_atom/1` when the attribute is configured with the `unsafe_to_atom?: true` constraint.\n\nFiltering such an attribute with attacker-controlled strings therefore interned a new, permanent atom for every distinct value. Atoms are never garbage collected and the BEAM caps the atom table, so an actor who can supply filter values for a public, filterable `:atom` attribute declared with `unsafe_to_atom?: true` can exhaust the atom table and crash the node (denial of service). AshPaperTrail is a notable example: its version resources expose a public, filterable `version_action_name` atom attribute with `unsafe_to_atom?: true` by default.\n\nThe fix adds a `coerce/2` to `Ash.Type.Atom` that never interns atoms — a comparison value is left as a string, since the type is stored and compared as a string. Setting the attribute from action input (`cast_input/2`, which still honors `unsafe_to_atom?`) is unchanged.\n\nThis issue affects ash: from 3.5.1 before 3.34.3."
                        }
                    ],
                    "value": "Ash stores :atom-typed attributes as strings and compares them as strings. When such an attribute is referenced in a filter, the comparison value is coerced through Ash.Type.Atom. Because the type defined no coerce/2 callback, coercion fell back to the default (cast_input/2), which calls String.to_atom/1 when the attribute is configured with the unsafe_to_atom?: true constraint.\n\nFiltering such an attribute with attacker-controlled strings therefore interned a new, permanent atom for every distinct value. Atoms are never garbage collected and the BEAM caps the atom table, so an actor who can supply filter values for a public, filterable :atom attribute declared with unsafe_to_atom?: true can exhaust the atom table and crash the node (denial of service). AshPaperTrail is a notable example: its version resources expose a public, filterable version_action_name atom attribute with unsafe_to_atom?: true by default.\n\nThe fix adds a coerce/2 to Ash.Type.Atom that never interns atoms — a comparison value is left as a string, since the type is stored and compared as a string. Setting the attribute from action input (cast_input/2, which still honors unsafe_to_atom?) is unchanged.\n\nThis issue affects ash: from 3.5.1 before 3.34.3."
                }
            ],
            "impacts": [
                {
                    "capecId": "CAPEC-130",
                    "descriptions": [
                        {
                            "lang": "en",
                            "value": "CAPEC-130 Excessive Allocation"
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "cvssV4_0": {
                        "Automatable": "NOT_DEFINED",
                        "Recovery": "NOT_DEFINED",
                        "Safety": "NOT_DEFINED",
                        "attackComplexity": "LOW",
                        "attackRequirements": "PRESENT",
                        "attackVector": "NETWORK",
                        "baseScore": 8.2,
                        "baseSeverity": "HIGH",
                        "privilegesRequired": "NONE",
                        "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: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-770",
                            "description": "CWE-770 Allocation of Resources Without Limits or Throttling",
                            "lang": "en",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "providerMetadata": {
                "orgId": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
                "shortName": "EEF",
                "dateUpdated": "2026-10-05T19:19:51.326Z"
            },
            "references": [
                {
                    "name": "EEF CNA record for CVE-2026-94201",
                    "tags": [
                        "related",
                        "third-party-advisory"
                    ],
                    "url": "https://cna.erlef.org/cves/CVE-2026-94201.html"
                },
                {
                    "name": "OSV record EEF-CVE-2026-94201",
                    "tags": [
                        "related"
                    ],
                    "url": "https://osv.dev/vulnerability/EEF-CVE-2026-94201"
                },
                {
                    "name": "Introducing commit 2970ba3 in ash-project/ash",
                    "tags": [
                        "related"
                    ],
                    "url": "https://github.com/ash-project/ash/commit/2970ba3bd5d36d6ad04c731ac87385375d457147"
                },
                {
                    "name": "Fix commit 5282f3f in ash-project/ash",
                    "tags": [
                        "patch"
                    ],
                    "url": "https://github.com/ash-project/ash/commit/5282f3f513053628cdd1bf2236ea22d975d934d4"
                }
            ],
            "source": {
                "discovery": "EXTERNAL"
            },
            "title": "Filtering an :atom attribute with unsafe_to_atom? can exhaust the BEAM atom table in Ash"
        },
        "adp": [
            {
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-10-06T13:41:07.117450Z",
                                "id": "CVE-2026-94201",
                                "options": [
                                    {
                                        "Exploitation": "none"
                                    },
                                    {
                                        "Automatable": "no"
                                    },
                                    {
                                        "Technical Impact": "partial"
                                    }
                                ],
                                "role": "CISA Coordinator",
                                "version": "2.0.3"
                            }
                        }
                    }
                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
                    "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
                    "shortName": "CISA-ADP",
                    "dateUpdated": "2026-10-06T13:41:22.142Z"
                }
            }
        ]
    }
}