High severity · published Sep 1, 2026
CVE-2026-74837
Unbounded atom creation from client-supplied RPC field names in AshTypescript field formatter
8.7
CVSS
0.5%
EPSS
No
On KEV
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 RPC field names.
AshTypescript.FieldFormatter.convert_to_field_atom/2 in lib/ash_typescript/field_formatter.ex converts a client-supplied field name to an atom with String.to_atom/1 when no matching atom already exists. It delegates first to parse_input_field/2, which resolves the name with String.to_existing_atom/1 and falls back to returning the plain string; convert_to_field_atom/2 then mints an atom from that string rather than treating the name as unknown.
RPC field selection reaches it for every requested field name through AshTypescript.Rpc.FieldProcessing.FieldSelector, which resolves each name before checking that the field exists, with no allowlist, length bound, or rate limit. Atoms are never garbage collected, so each distinct name mints a permanent one and the VM aborts once the atom table limit is reached. A field name over 255 characters additionally raises an uncaught SystemLimitError.
This issue affects ash_typescript: from 0.1.0 before 0.18.0.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 46% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AS
ash_typescript · ash-project
0.1.0 before 0.18.0; 1a3d4c343430c8e4784acfcd33122a807fafa086 before df95df4b9afdca5e5bbce32dbd566ccc49a7f14b · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-74837
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-74837
cna.erlef.org
https://cna.erlef.org/cves/CVE-2026-74837.html
github.com
https://github.com/ash-project/ash_typescript/commit/df95df4b9afdca5e5bbce32dbd566ccc49a7f14b
github.com
https://github.com/ash-project/ash_typescript/security/advisories/GHSA-mhxc-mhqx-3v28
osv.dev
https://osv.dev/vulnerability/EEF-CVE-2026-74837
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