CVE-2026-45398
HIGH EPSS 24.8%
Published May 15, 20261mo ago · Modified Jun 17, 20262w ago
7.5 CVSS 3.1
Published May 15, 2026 1mo ago
Last Modified Jun 17, 2026 2w ago
Description
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.5, _validate_collection_access() checks the user-memory-* and file-* collection name prefixes but does not check knowledge base collections, which use raw UUIDs as collection names. Any authenticated user who knows a private knowledge base UUID can read its content through the retrieval query endpoints, even though the knowledge API correctly denies that user access. The same gap affects the retrieval write endpoints (/process/text, /process/file, /process/files/batch, /process/web, /process/youtube), allowing an attacker to inject content into or overwrite another user's knowledge base. This vulnerability is fixed in 0.9.5.
CVSS Details
Base Score
Exploitability
Impact
Vector string
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H Attack Vector Network
Attack Complexity High
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality High
Integrity High
Availability High
Threat Intelligence
EPSS Exploit Probability
24.8% percentile
Exploit & Patch Status
Public Exploit Known
Patch Available
Weaknesses 1
CWE-639
Affected Products 1
| Vendor | Product | Version | Range |
|---|---|---|---|
| openwebui | open_webui | * | <0.9.5 |
References 3
- github.com https://github.com/open-webui/open-webui/pull/22109
- github.com https://github.com/open-webui/open-webui/releases/tag/v0.9.5
- github.com https://github.com/open-webui/open-webui/security/advisories/GHSA-4g37-7p2c-38r9
Remediation
- github.com https://github.com/open-webui/open-webui/pull/22109