# CVE-2026-82730: Authorization-redacted field values disclosed through AshTypescript result normalization

> An attacker can read sensitive attribute values denied by field policies due to improper serialization of forbidden field markers in AshTypescript RPC results.

- **Severity:** High 8.2 (`CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 1 Sep 2026
- **Updated:** 1 Sep 2026
- **Also known as:** EEF-CVE-2026-82730, GHSA-6929-rjmh-4x62

## What is CVE-2026-82730?

CVE-2026-82730 is a high-severity vulnerability in ash-project ash_typescript, published on 1 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Incorrect Authorization vulnerability in ash-project ash_typescript allows an unauthorized RPC caller to read attribute values that Ash field policies denied.

When a field policy denies an attribute, Ash substitutes %Ash.ForbiddenField{}, which retains the real value in original_value because embedded resources must remain writable, and hides it from Inspect rather than removing it. AshTypescript.Rpc.ResultProcessor strips these markers to nil on its template-driven paths, but normalize_primitive/1 in lib/ash_typescript/rpc/result_processor.ex had no such clause, so a marker fell through to the generic struct branch which calls Map.from_struct/1 and serializes every key, original_value included. The denied value is returned to the caller inside the marker that represents its own denial.

The simplest trigger is an action returning an embedded resource as a map, which routes through normalize_resource_struct/2 with an empty template. normalize_value_for_json/1 is a public, unguarded entry point to the same path.

This issue affects ash_typescript: from 0.11.0 before 0.18.0.

Weakness: CWE-863 (Incorrect Authorization)

## Which versions are affected by CVE-2026-82730?

1 open source package ship an affected version, including ash_typescript.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `ash_typescript` | Hex | From 0.11.0 | 0.18.0 |

## How do I fix CVE-2026-82730?

Upgrade ash_typescript to 0.18.0 or later.

## Is CVE-2026-82730 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-82730 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-82730 and fix it if it is affected.

What it is: CVE-2026-82730 is a high-severity vulnerability in ash-project ash_typescript, published on 1 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-82730 exists.

Affected packages and fixed versions:
- ash_typescript (Hex): affected from 0.11.0; fixed in 0.18.0

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-82730/ (Markdown: https://insights.sbomify.com/CVE-2026-82730/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-82730
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-82730
- OSV: https://osv.dev/vulnerability/CVE-2026-82730

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-82730/
Summaries are generated and may contain mistakes; the official description above is the record.