Vulnerability · Published Sep 1, 2026 · Assigned by EEF
CVE-2026-82747Ash.Policy.Authorizer returns records denied by a runtime read policy to any actor
Medium 5.9
In plain English
A medium-severity incorrect authorization in ash from ash-project. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 6% of all known vulnerabilities).
Official description
Incorrect Authorization vulnerability in ash-project ash returns records that a runtime read policy denies to any actor. When a resource has an access_type :runtime read policy (a check evaluated per record rather than compiled to a filter), Ash.Policy.Authorizer decides each record in check_result/1 (lib/ash/policy/authorizer/authorizer.ex) by discarding impossible policy scenarios and inspecting what remains. When every scenario for a record was impossible, meaning no policy can authorize it and it must be forbidden, the empty-scenario branch instead kept the record ({[record | data], authorizer, any_forbidden?}) and returned it as authorized. As a result, records the runtime read policy denies are returned to any actor. The fix forbids a record whose scenarios are all impossible. This issue affects ash: from 3.4.44 before 3.32.2.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| ash-project | ash | 3.4.44 – before 3.32.2 |
| ash-project | ash | f4a8ff53fd3b974468d73685cd3fc842ef893de3 – before 6eddb8ab26e45023faf0c79ebd152bb40aefda02 |
Weakness: CWE-863 · Vector: CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N