EEF-CVE-2026-77856
Unbounded atom creation from typed struct field names in AshTypescript field selector
Quick fix
EEF-CVE-2026-77856 — ash_typescript: upgrade to the fixed version with the command below.
mix deps.update ash_typescriptDetails
## Summary
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.
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.
This issue affects ash\_typescript: from 0.11.0 before 0.18.0.
## Configuration
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.
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