CVE-2026-81853 (GCVE-0-2026-81853)
Vulnerability from cvelistv5 – Published: 2026-08-31 02:31 – Updated: 2026-08-31 02:31
VLAI
EPSS
VEX
Title
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.
Severity
CWE
- CWE-639 - Authorization Bypass Through User-Controlled Key
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://github.com/ash-project/ash_admin/security… | vendor-advisoryrelated |
| https://cna.erlef.org/cves/CVE-2026-81853.html | related |
| https://osv.dev/vulnerability/EEF-CVE-2026-81853 | related |
| https://github.com/ash-project/ash_admin/commit/3… | patch |
Impacted products
2 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| ash-project | ash_admin |
Affected:
0.1.0 , < 1.3.1
(semver)
cpe:2.3:a:ash-project:ash_admin:*:*:*:*:*:*:*:* |
||
| ash-project | ash_admin |
Affected:
98b03baa8422b94dd13e305bf08b8ee3f7232c7b , < 3c3e905d47f1155dcc1ca3fb347348b05a66065a
(git)
cpe:2.3:a:ash-project:ash_admin:*:*:*:*:*:*:*:* |
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"title": "AshAdmin composite primary key decoding accepts arbitrary fields, enabling a secret-attribute oracle"
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}
}
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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