CVE-2026-77856 — Unbounded atom creation from typed struct field names in AshTypescript field selector
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 …
Published: 2026-09-01 · CVSS: 8.2 · CVSS 4.0
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.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7