CVE-2026-81853
Authorization Bypass Through User-Controlled Key vulnerability in ash-project ash_admin turns a record-lookup URL into an equality oracle over sensitive attributes.
Does this matter?
Lower severity and a low EPSS score (0.26%). Track it; it rarely justifies an emergency change on its own.
Description
Authorization Bypass Through User-Controlled Key vulnerability in ash-project ash_admin turns a record-lookup URL into an equality oracle over sensitive attributes. AshAdmin.Helpers.decode_primary_key/2 decodes the composite-primary-key form (Base64 plus ETF) and returns the decoded map verbatim as the lookup filter, without checking that its keys are the resource's primary-key fields. The deserialization guards bound size, block new atoms and funs, and reject nested expressions, but none restricts which fields come back, and :safe still allows any already-interned attribute name. An attacker can therefore encode %{api_token: "guess"} and have it spliced into the lookup filter, brute-forcing a sensitive attribute value (API token, reset token) one equality guess at a time; Map.to_list/1 also accepts structs, yielding a bogus __struct__ key. The fix rejects any decoded key that is not a real primary-key field. This issue affects ash_admin: from 0.1.0 before 1.3.1.
- CVSS 4.0
- 2.3 LOWCVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:N/VA:N/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/M
- EPSS
- 0.26% probability · 18th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-639
- Source
- 6b3ad84c-e1a6-4bf7-a703-f496b71e49db
References
- https://cna.erlef.org/cves/CVE-2026-81853.html
- https://github.com/ash-project/ash_admin/commit/3c3e905d47f1155dcc1ca3fb347348b05a66065a
- https://github.com/ash-project/ash_admin/security/advisories/GHSA-jxr8-hpv2-qp38
- https://osv.dev/vulnerability/EEF-CVE-2026-81853
- https://github.com/ash-project/ash_admin/security/advisories/GHSA-jxr8-hpv2-qp38
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.