Authorization bypass via persisted union tag confusion
Published Sep 1, 2026 · Updated Sep 1, 2026
Improper input validation in Ash 2.14.18 through 3.32.1 allows attackers to bypass union-member validation via a forged stored tag. Ash.Type.Union.dump_to_native/2 persists a submitted tag instead of forcing the configured tag for storage: :map_with_tag, so reads select an incompatible union member. Exploitation requires an application path that accepts attacker-controlled union values in this storage mode; successful manipulation bypasses the actual member constraints and tag-based authorization.
Summary
What happened
Improper input validation in Ash 2.14.18 through 3.32.1 allows attackers to bypass union-member validation via a forged stored tag. Ash.Type.Union.dump_to_native/2 persists a submitted tag instead of forcing the configured tag for storage: :map_with_tag, so reads select an incompatible union member. Exploitation requires an application path that accepts attacker-controlled union values in this storage mode; successful manipulation bypasses the actual member constraints and tag-based authorization.
The record
- CVE
- CVE-2026-82741
- Published
- Sep 1, 2026
- Updated
- Sep 1, 2026
- Vendor
- Ash Framework
- Product
- Ash
- Classifications
- CWE-1287, CAPEC-153, T1565.001
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- Sep 1, 2026CVE publishedPublication date reported by the CVE source.
- Sep 1, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=2.14.18 <3.32.2
- Affected versionversion=b0bd2d23d979e731610327636f51da4981fcef68 <8dbdaecd0f115f52e7c3f9a3e798617d6fbf5f7d
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What is affected?
Published CVSS scores
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Attacks
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Your stack
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