Medium severity · published Sep 1, 2026
CVE-2026-82747
Ash.Policy.Authorizer returns records denied by a runtime read policy to any actor
5.9
CVSS
0.2%
EPSS
No
On KEV
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.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 6% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AS
ash · ash-project
3.4.44 before 3.32.2; f4a8ff53fd3b974468d73685cd3fc842ef893de3 before 6eddb8ab26e45023faf0c79ebd152bb40aefda02 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-82747
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-82747
cna.erlef.org
https://cna.erlef.org/cves/CVE-2026-82747.html
github.com
https://github.com/ash-project/ash/commit/6eddb8ab26e45023faf0c79ebd152bb40aefda02
github.com
https://github.com/ash-project/ash/security/advisories/GHSA-4259-gvr2-4xhq
osv.dev
https://osv.dev/vulnerability/EEF-CVE-2026-82747
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