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NVD / CVE Program· CNA EEF

CVE-2026-74837: Unbounded atom creation from client-supplied RPC field names in AshTypescript field formatter

HighCVSS 8.7 · v4.0—No exploit Fix available

Noroxi assessment

Priority: Monitor (action score 34/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.54% (FIRST EPSS).
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • According to CISA the attack is automatable: targets can be found by mass scanning.
  • Fixed version: ash-project ash_typescript 0.18.0, df95df4b9afdca5e5bbce32dbd566ccc49a7f14b.

Low priority for now. Upgrade to ash-project ash_typescript 0.18.0, df95df4b9afdca5e5bbce32dbd566ccc49a7f14b or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

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.

Published
Aug 31, 2026
Updated
Sep 1, 2026
EPSS
0.5% · 46th percentile

Report tools

JSON

Action score

34

Monitor

Low priority for now.

CVSS
34 / 40 · 8.7 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.5%

CISA SSVC decision

Exploitation
proof of concept
Automatable
yes
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · EEF
8.7
NVD has not scored this yet; the score shown is the CNA’s.

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2026-74837

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

—

Versions reported by the vendor

Affected version ranges reported by the assigning authority (EEF). Independent of NVD's CPE analysis and usually ahead of it.

  • ash-project ash_typescript

    • 0.1.0 and later · before 0.18.0affected · semver
    • 1a3d4c343430c8e4784acfcd33122a807fafa086 and later · before df95df4b9afdca5e5bbce32dbd566ccc49a7f14baffected · git

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Hexash_typescriptfrom 0.1.0 · before 0.18.00.18.0

Same product

ash-project: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-82730Authorization-redacted field values disclosed through AshTypescript result normalization
    32Monitor
  • CVE-2026-77856Unbounded atom creation from typed struct field names in AshTypescript field selector
    32Monitor
  • CVE-2026-105283Internal error terms inspected into AshTypescript RPC error responses
    25Monitor

Published before and after this one in the same product

  • Later →CVE-2026-77950Aug 31, 2026 · RPC error handler fails open in AshTypescript, disclosing unredacted errors
    25Monitor
  • Later →CVE-2026-82731Aug 31, 2026 · Unescaped path parameters in AshTypescript generated TypeScript client allow request redirection
    9Monitor
  • Later →CVE-2026-82732Aug 31, 2026 · Declared argument constraints not enforced on AshTypescript typed controller routes
    25Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
ash-project ash_typescript0.18.0Vendor (CNA)
ash-project ash_typescriptdf95df4b9afdca5e5bbce32dbd566ccc49a7f14bVendor (CNA)
Hex:ash_typescript0.18.0Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

  • CVE-2026-778560 days apartUnbounded atom creation from typed struct field names in AshTypescript field selector
    32Monitor

Not on record for this CVE: public bounty program.

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
Integrity
Availability
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
X

Weakness class (CWE)

CWE-770 · Allocation of Resources Without Limits or Throttling

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/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

nvd-secondary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

References

Show all references (3 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records