{"id":"CVE-2026-77856","aliases":["EEF-CVE-2026-77856","EUVD-2026-68924","GHSA-rj47-h936-4cxw"],"status":"published","title":"Unbounded atom creation from typed struct field names in AshTypescript field selector","description":"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.","severity":{"version":"4.0","score":8.2,"vector":"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","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00547,"percentile":0.46172,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-770"],"published":"2026-09-01T02:08:46Z","modified":"2026-10-28T02:31:08Z","fixes":[{"ecosystem":"Hex","package":"ash_typescript","fixed_in":["0.18.0"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Hex","package":"ash_typescript","ranges":[{"type":"SEMVER","events":[{"introduced":"0.11.0"},{"fixed":"0.18.0"}]}],"versions":["0.11.0","0.11.1","0.11.2","0.11.3","0.11.4","0.11.5","0.11.6","0.12.0","0.12.1","0.13.0","0.13.1","0.13.2","0.14.0","0.14.1","0.14.2","0.14.3","0.14.4","0.15.0","0.15.1","0.15.2","0.15.3","0.16.0","0.17.0","0.17.1","0.17.2","0.17.3"]}],"products":[{"vendor":"ash-project","product":"ash_typescript"}],"references":[{"url":"https://github.com/ash-project/ash_typescript/security/advisories/GHSA-rj47-h936-4cxw","tags":["related","vendor-advisory","exploit","advisory"]},{"url":"https://cna.erlef.org/cves/CVE-2026-77856.html","tags":["related","web"]},{"url":"https://osv.dev/vulnerability/EEF-CVE-2026-77856","tags":["related","web"]},{"url":"https://github.com/ash-project/ash_typescript/commit/0ab5c83a7df28d51a6de1fb9b859a142b2b12919","tags":["patch","fix"]},{"url":"https://github.com","tags":["web"]},{"url":"https://repo.hex.pm","tags":["web"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/77xxx/CVE-2026-77856.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-77856","tags":["advisory"]},{"url":"https://github.com/ash-project/ash_typescript","tags":["package"]},{"url":"https://hex.pm/packages/ash_typescript","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-77856","title":"Unbounded atom creation from typed struct field names in AshTypescript field selector","description":"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.","status":"published","published":"2026-09-01T02:08:46.189Z","modified":"2026-09-01T14:49:22.592Z","cvss":[{"version":"4.0","score":8.2,"vector":"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","level":"high","assessor":"cna"}],"cwes":["CWE-770"],"updated_at":"2026-11-02T14:20:15.712761Z"}],"euvd":[{"id":"EUVD-2026-68924","description":"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.","status":"published","published":"2026-09-01T02:08:46Z","modified":"2026-09-01T14:49:22Z","cvss":[{"version":"4.0","score":8.2,"vector":"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","level":"high"}],"updated_at":"2026-11-02T18:01:18.264709Z"}],"nvd":[{"id":"CVE-2026-77856","description":"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.","status":"published","published":"2026-09-01T03:16:51.5Z","modified":"2026-09-01T21:15:00.147Z","cvss":[{"version":"4.0","score":8.2,"vector":"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/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","level":"high","assessor":"secondary"}],"cwes":["CWE-770"],"updated_at":"2026-11-02T14:12:42.691315Z"}],"osv":[{"id":"CVE-2026-77856","title":"Unbounded atom creation from typed struct field names in AshTypescript field selector","description":"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.","status":"published","published":"2026-09-01T02:08:46.189Z","modified":"2026-10-28T02:31:08.353530066Z","cvss":[{"version":"4.0","score":8.2,"vector":"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","level":"high"}],"cwes":["CWE-770"],"updated_at":"2026-11-02T15:45:17.44708Z"},{"id":"EEF-CVE-2026-77856","title":"Unbounded atom creation from typed struct field names in AshTypescript field selector","description":"## Summary\n\nAllocation 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.\n\n## Configurations\n\nThe 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`.","status":"published","published":"2026-09-01T02:08:46.189Z","modified":"2026-09-08T03:45:06.999521122Z","cvss":[{"version":"4.0","score":8.2,"vector":"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","level":"high"}],"cwes":["CWE-770"],"updated_at":"2026-11-02T15:46:33.520522Z"}]}}