CVE-2026-81853
AshAdmin composite primary key decoding accepts arbitrary fields, enabling a secret-attribute oracle
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
2.3
AshAdmin composite primary key decoding accepts arbitrary fields, enabling a secret-attribute oracle
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.
- Record
CVE-2026-81853- CVSS 4.0
- 2.3 Low
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N - Weakness
- CWE-639
- Updated
- 2026-11-02
EUVDEUVD-2026-68330
2.3
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.
- Record
EUVD-2026-68330- CVSS 4.0
- 2.3 Low
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N - Updated
- 2026-11-02
NVD
2.3
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.
- Record
CVE-2026-81853- CVSS 4.0
- 2.3 Low
CVSS: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/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - Weakness
- CWE-639
- Updated
- 2026-11-02
OSV
2.3
AshAdmin composite primary key decoding accepts arbitrary fields, enabling a secret-attribute oracle
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.
- Record
CVE-2026-81853- CVSS 4.0
- 2.3 Low
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N - Weakness
- CWE-639
- Updated
- 2026-11-02
OSVEEF-CVE-2026-81853
2.3
AshAdmin composite primary key decoding accepts arbitrary fields, enabling a secret-attribute oracle
Summary
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.
Configurations
The resource has a composite primary key, and the deployment relies on AshAdmin's authorization (a custom actor plug and policies) so that reading otherwise-restricted attribute values crosses a boundary.
- Record
EEF-CVE-2026-81853- CVSS 4.0
- 2.3 Low
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N - Weakness
- CWE-639
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
ash_adminHex |
0.1.0 up to 1.3.1, plus listed versions 0.1.20.1.30.1.50.1.60.10.0 Show 45 moreShow less0.10.10.10.100.10.10-rc.00.10.10-rc.10.10.110.10.120.10.20.10.30.10.40.10.50.10.60.10.70.10.80.10.90.11.00.11.10.11.100.11.110.11.20.11.30.11.40.11.50.11.60.11.70.11.80.11.90.12.00.12.10.12.20.12.30.12.40.12.50.12.60.13.00.13.10.13.100.13.110.13.120.13.130.13.140.13.150.13.160.13.170.13.180.13.19 |
1.3.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, published | EUVD | |
| first indexed | CVE List, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-81853 is a low vulnerability (CVSS 2.3) in Ash-project Ash Admin, published August 31, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.45%, the 39th percentile. Fixed in ash_admin 1.3.1.
References
Left out here: 68 versions. The JSON record has them.