Declared argument constraints not enforced on AshTypescript typed controller routes
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- Present
- Impact type
- —
- Confidentiality · integrity · availability
- None · Low · None
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA.
Summary
Improper Input Validation vulnerability in ash-project ash_typescript allows a remote attacker to submit argument values outside a declared allowlist or bound on typed-controller routes. AshTypescript.TypedController.RequestHandler in lib/ash_typescript/typed_controller/request_handler.ex calls Ash.Type.cast_input/3 and treats an {:ok, cast} result as fully validated. In Ash these are separate steps: cast_input/3 only coerces the term, while every constraint declared on the argument is applied by Ash.Type.apply_constraints/3, which this path never calls. Constraints such as one_of, max_length, min and max, and match are therefore inert, so a value outside a declared allowlist is accepted and passed to the route handler. Codegen renders the same constraints into the generated TypeScript types, so an allowlist appears enforced to a TypeScript caller while any other HTTP client ignores it. Empty-string to nil normalization also lives in apply_constraints, so the allow_nil?: false check accepts "" for a required argument. Where a constraint gates a role, a status, or a sort direction, this becomes a privilege or state-machine bypass. This issue affects ash_typescript: from 0.15.0 before 0.18.0.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| ash-project | ash_typescript | 0.15.0 to before 0.18.0 | 0.18.0 | Patch available | CNA |
- ash_typescript Vendorash-project Affected 0.15.0 to before 0.18.0 Fixed in 0.18.0 Patch available CNA
CPE names CNA · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:ash-project:ash_typescript:*:*:*:*:*:*:*:* | — | — | — |
- cpe:2.3:a:ash-project:ash_typescript:*:*:*:*:*:*:*:* Versions — — ·—
Remediation
- Fix · CNA ash_typescript (ash-project) Fixed in 0.18.0
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
ash-project ash_typescript 0.18.0
7 records Highest priority Priority HIGH 3 HIGH, 4 MEDIUM
Other records, highest priority first
- TI-2026-52572 Unbounded atom creation from client-supplied RPC field names in AshTypescript field formatterPriority HIGH 77
- TI-2026-57048 Authorization-redacted field values disclosed through AshTypescript result normalizationPriority HIGH 69
- TI-2026-54210 Unbounded atom creation from typed struct field names in AshTypescript field selectorPriority HIGH 69
Timeline
- 2026-10-02 Threatist record created from CVE-2026-82732
References
More ash-project vulnerabilities
- TI-2026-56298 Query-complexity limit bypass via first/last pagination arguments in AshGraphql enables denial of service CVSS 4.0HIGH 8.7
- TI-2026-52572 Unbounded atom creation from client-supplied RPC field names in AshTypescript field formatter CVSS 4.0HIGH 8.7
- TI-2026-57010 Path traversal in AshAdmin file uploads via unsanitized client filename CVSS 4.0HIGH 8.3
- TI-2026-26840 Ash Framework: Ash.Type.Module.cast_input/2 atom exhaustion via unchecked Module.concat allows BEAM VM crash CVSS 4.0HIGH 8.2
- TI-2026-54252 EEx template evaluation of prompt content in AshAi enables remote code execution CVSS 4.0HIGH 8.9
- TI-2026-54208 Stored XSS in AshAdmin relationship typeahead via unescaped label_field content CVSS 4.0HIGH 8.4
Sources
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences