Read the docs
TI-2026-33187 Aliases CVE-2026-45398GHSA-4g37-7p2c-38r9

Open WebUI: IDOR - Retrieval API Bypasses Knowledge Base Access Controls

Priority HIGH 68CWE-639Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
High
Impact type
Security bypass
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-639.

Summary

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00331 26th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed open-webui (open-webui): 0.9.5open-webui (PyPI): 0.9.5

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
open-webuiopen-webuibefore 0.9.50.9.5Patch availableCNA
—open-webui (PyPI)before 0.9.50.9.5Patch availableGHSA-4g37-7p2c-38r9
  • open-webui Vendoropen-webui Affected before 0.9.5 Fixed in 0.9.5 Patch available CNA
  • open-webui (PyPI) Vendor— Affected before 0.9.5 Fixed in 0.9.5 Patch available GHSA-4g37-7p2c-38r9

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:openwebui:open_webui:*:*:*:*:*:*:*:*before 0.9.5Vulnerableopen-webui
  • cpe:2.3:a:openwebui:open_webui:*:*:*:*:*:*:*:* Versions before 0.9.5 Vulnerable ·open-webui

Remediation

  • Fix · CNA open-webui (open-webui) Fixed in 0.9.5
  • Fix · GHSA-4g37-7p2c-38r9 open-webui (PyPI) Fixed in 0.9.5 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-45398
  2. 2026-10-03 Alias added: GHSA-4g37-7p2c-38r9

References

Exploit 1

Patch 1

Advisory 1

Other 2

  • TI-2024-06216 Open WebUI Arbitrary File Upload + Path Traversal CVSS 3.1HIGH 8.8
  • TI-2024-07467 Improper Authentication in open-webui/open-webui CVSS 3.1HIGH 8.2
  • TI-2026-42359 Open WebUI: Cross-user code-interpreter and tool execution via unvalidated Socket.IO event-caller session_id CVSS 3.1CRITICAL 9.0
  • TI-2026-40759 open-webui - Remote Code Execution via CORS Misconfiguration and Session Validation CVSS 4.0CRITICAL 9.0
  • TI-2024-07431 Cross-site Scripting (XSS) in open-webui/open-webui CVSS 3.0CRITICAL 9.0
  • TI-2026-60021 Open WebUI: Same-origin XSS to account takeover via terminal port-preview iframe hardcoding allow-same-origin CVSS 3.1HIGH 8.7
See all 154 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences