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.
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.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| ash-project | ash_typescript | 0.11.0 – < 0.18.0 | 0.18.0 |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| Hex | ash_typescript | >= 0.11.0, < 0.18.0 | 0.18.0 | EEF-CVE-2026-77856 |
References
- https://github.com/ash-project/ash_typescript/security/advisories/GHSA-rj47-h936-4cxw related vendor-advisory
- https://cna.erlef.org/cves/CVE-2026-77856.html related
- https://osv.dev/vulnerability/EEF-CVE-2026-77856 related
- https://github.com/ash-project/ash_typescript/commit/0ab5c83a7df28d51a6de1fb9b859a142b2b12919 patch