{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-77856",
        "assignerOrgId": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
        "state": "PUBLISHED",
        "assignerShortName": "EEF",
        "dateReserved": "2026-08-30T17:30:01.406Z",
        "datePublished": "2026-09-01T02:08:46.189Z",
        "dateUpdated": "2026-09-01T02:08:46.189Z"
    },
    "containers": {
        "cna": {
            "affected": [
                {
                    "collectionURL": "https://repo.hex.pm",
                    "cpes": [
                        "cpe:2.3:a:ash-project:ash_typescript:*:*:*:*:*:*:*:*"
                    ],
                    "defaultStatus": "unaffected",
                    "modules": [
                        "'Elixir.AshTypescript.Rpc.FieldProcessing.FieldSelector'",
                        "'Elixir.AshTypescript.Rpc'"
                    ],
                    "packageName": "ash_typescript",
                    "packageURL": "pkg:hex/ash_typescript",
                    "product": "ash_typescript",
                    "programFiles": [
                        "lib/ash_typescript/rpc/field_processing/field_selector.ex",
                        "lib/ash_typescript/rpc.ex"
                    ],
                    "programRoutines": [
                        {
                            "name": "'Elixir.AshTypescript.Rpc.FieldProcessing.FieldSelector':resolve_typed_struct_field/2"
                        },
                        {
                            "name": "'Elixir.AshTypescript.Rpc':run_action/3"
                        }
                    ],
                    "repo": "https://github.com/ash-project/ash_typescript",
                    "vendor": "ash-project",
                    "versions": [
                        {
                            "lessThan": "0.18.0",
                            "status": "affected",
                            "version": "0.11.0",
                            "versionType": "semver"
                        }
                    ]
                },
                {
                    "collectionURL": "https://github.com",
                    "cpes": [
                        "cpe:2.3:a:ash-project:ash_typescript:*:*:*:*:*:*:*:*"
                    ],
                    "defaultStatus": "unaffected",
                    "modules": [
                        "'Elixir.AshTypescript.Rpc.FieldProcessing.FieldSelector'",
                        "'Elixir.AshTypescript.Rpc'"
                    ],
                    "packageName": "ash-project/ash_typescript",
                    "packageURL": "pkg:github/ash-project/ash_typescript",
                    "product": "ash_typescript",
                    "programFiles": [
                        "lib/ash_typescript/rpc/field_processing/field_selector.ex",
                        "lib/ash_typescript/rpc.ex"
                    ],
                    "programRoutines": [
                        {
                            "name": "'Elixir.AshTypescript.Rpc.FieldProcessing.FieldSelector':resolve_typed_struct_field/2"
                        },
                        {
                            "name": "'Elixir.AshTypescript.Rpc':run_action/3"
                        }
                    ],
                    "repo": "https://github.com/ash-project/ash_typescript",
                    "vendor": "ash-project",
                    "versions": [
                        {
                            "lessThan": "0ab5c83a7df28d51a6de1fb9b859a142b2b12919",
                            "status": "affected",
                            "version": "7c3d30896f2f9a54edea17e3787549776b1b288d",
                            "versionType": "git"
                        }
                    ]
                }
            ],
            "configurations": [
                {
                    "lang": "en",
                    "supportingMedia": [
                        {
                            "base64": false,
                            "type": "text/html",
                            "value": "<p>The application exposes an AshTypescript RPC endpoint over HTTP and has at least one resource field backed by an <code>Ash.TypedStruct</code>, so that client-supplied names reach <code>resolve_typed_struct_field/2</code>.</p>"
                        },
                        {
                            "base64": false,
                            "type": "text/markdown",
                            "value": "The application exposes an AshTypescript RPC endpoint over HTTP and has at least one resource field backed by an `Ash.TypedStruct`, so that client-supplied names reach `resolve_typed_struct_field/2`."
                        }
                    ],
                    "value": "The application exposes an AshTypescript RPC endpoint over HTTP and has at least one resource field backed by an Ash.TypedStruct, so that client-supplied names reach resolve_typed_struct_field/2."
                }
            ],
            "cpeApplicability": [
                {
                    "nodes": [
                        {
                            "cpeMatch": [
                                {
                                    "criteria": "cpe:2.3:a:ash-project:ash_typescript:*:*:*:*:*:*:*:*",
                                    "versionEndExcluding": "0.18.0",
                                    "versionStartIncluding": "0.11.0",
                                    "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": "Torkild Gundersen Kjevik / Ash Project"
                },
                {
                    "lang": "en",
                    "type": "coordinator",
                    "value": "Jonatan Männchen / EEF"
                }
            ],
            "descriptions": [
                {
                    "lang": "en",
                    "supportingMedia": [
                        {
                            "base64": false,
                            "type": "text/html",
                            "value": "<p>Allocation of Resources Without Limits or Throttling vulnerability in ash-project ash_typescript allows an unauthenticated attacker to exhaust the BEAM atom table and abort the node via client-supplied typed struct field names.</p>\n<p><code>resolve_typed_struct_field/2</code> in <code>lib/ash_typescript/rpc/field_processing/field_selector.ex</code> looks a client-supplied field name up in the typed struct's reverse map and, when it finds no match, falls back to <code>String.to_atom/1</code>. Because this runs before any field-existence check, an unresolvable name mints a permanent atom rather than being rejected as unknown. Atoms are never garbage collected, so a request carrying many distinct names on a typed struct field grows the atom table until the VM aborts at its limit.</p>\n<p>This issue affects ash_typescript: from 0.11.0 before 0.18.0.</p>"
                        },
                        {
                            "base64": false,
                            "type": "text/markdown",
                            "value": "Allocation of Resources Without Limits or Throttling vulnerability in ash-project ash_typescript allows an unauthenticated attacker to exhaust the BEAM atom table and abort the node via client-supplied typed struct field names.\n\n`resolve_typed_struct_field/2` in `lib/ash_typescript/rpc/field_processing/field_selector.ex` looks a client-supplied field name up in the typed struct's reverse map and, when it finds no match, falls back to `String.to_atom/1`. Because this runs before any field-existence check, an unresolvable name mints a permanent atom rather than being rejected as unknown. Atoms are never garbage collected, so a request carrying many distinct names on a typed struct field grows the atom table until the VM aborts at its limit.\n\nThis issue affects ash_typescript: from 0.11.0 before 0.18.0."
                        }
                    ],
                    "value": "Allocation of Resources Without Limits or Throttling vulnerability in ash-project ash_typescript allows an unauthenticated attacker to exhaust the BEAM atom table and abort the node via client-supplied typed struct field names.\n\nresolve_typed_struct_field/2 in lib/ash_typescript/rpc/field_processing/field_selector.ex looks a client-supplied field name up in the typed struct's reverse map and, when it finds no match, falls back to String.to_atom/1. Because this runs before any field-existence check, an unresolvable name mints a permanent atom rather than being rejected as unknown. Atoms are never garbage collected, so a request carrying many distinct names on a typed struct field grows the atom table until the VM aborts at its limit.\n\nThis issue affects ash_typescript: from 0.11.0 before 0.18.0."
                }
            ],
            "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": "2026-09-01T02:08:46.189Z"
            },
            "references": [
                {
                    "tags": [
                        "related",
                        "vendor-advisory"
                    ],
                    "url": "https://github.com/ash-project/ash_typescript/security/advisories/GHSA-rj47-h936-4cxw"
                },
                {
                    "tags": [
                        "related"
                    ],
                    "url": "https://cna.erlef.org/cves/CVE-2026-77856.html"
                },
                {
                    "tags": [
                        "related"
                    ],
                    "url": "https://osv.dev/vulnerability/EEF-CVE-2026-77856"
                },
                {
                    "tags": [
                        "patch"
                    ],
                    "url": "https://github.com/ash-project/ash_typescript/commit/0ab5c83a7df28d51a6de1fb9b859a142b2b12919"
                }
            ],
            "source": {
                "discovery": "EXTERNAL"
            },
            "title": "Unbounded atom creation from typed struct field names in AshTypescript field selector"
        }
    }
}