Authenticated cross-tenant workflow execution via unchecked UUID references
Published May 12, 2026 · Updated May 12, 2026
Incorrect authorization in Heym before 0.0.21 allows remote authenticated users to execute workflows belonging to other users. The collect_referenced_workflows path loads executeWorkflowId and agent subWorkflowIds targets into its cache without checking the actor's access. A valid account and another workflow's UUID are required; exploitation exposes workflow outputs and runs nodes with the victim workflow's side effects.
Summary
What happened
Incorrect authorization in Heym before 0.0.21 allows remote authenticated users to execute workflows belonging to other users. The collect_referenced_workflows path loads executeWorkflowId and agent subWorkflowIds targets into its cache without checking the actor's access. A valid account and another workflow's UUID are required; exploitation exposes workflow outputs and runs nodes with the victim workflow's side effects.
The record
- CVE
- CVE-2026-45226
- Published
- May 12, 2026
- Updated
- May 12, 2026
- Vendor
- Heym
- Product
- Heym
- Classifications
- CWE-863
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- May 12, 2026CVE publishedPublication date reported by the CVE source.
- May 12, 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?
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- Affected versionversion=0 <0.0.21
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
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Weakness, pattern, technique
Public exploit references
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Technologies
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Your stack
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