CVE-2026-45671 (GCVE-0-2026-45671)
Vulnerability from cvelistv5 – Published: 2026-05-15 19:13 – Updated: 2026-05-19 03:55
VLAI
EPSS
VEX
Title
Open WebUI: shared-chat branch ignores access_type, allowing unauthorized file deletion
Summary
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.0, any authenticated user can permanently delete files owned by other users via DELETE /api/v1/files/{id} when the target file is referenced in any shared chat. The has_access_to_file() authorization gate unconditionally grants access through its shared-chat branch. It checks neither the requesting user's identity nor the type of operation being performed. File UUIDs (which would otherwise be impractical to guess) are disclosed to any user with read access to a knowledge base via GET /api/v1/knowledge/{id}/files. This vulnerability is fixed in 0.9.0.
Severity
SSVC
Exploitation: poc
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-18 00:00 UTC
CWE
- CWE-639 - Authorization Bypass Through User-Controlled Key
Assigner
GitHub_M
CNA
References
1 reference
| URL | Tags |
|---|---|
| https://github.com/open-webui/open-webui/security… | x_refsource_CONFIRM |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| open-webui | open-webui |
Affected:
< 0.9.0
|
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Sightings
| Author | Source | Type | Date | Other |
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Nomenclature
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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.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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