High 7.5Published May 15, 2026

CVE-2026-45398Open WebUI: IDOR - Retrieval API Bypasses Knowledge Base Access Controls

Updated under an hour ago (Oct 26, 2026, 3:40 PM ET)

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No exploitation reported and no EPSS estimate yet.

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Every CVE for open-webui

Exploited in the last 30 days

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: 7.5 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Weakness (CWE): CWE-639
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Analyzed
Record last updated: May 18, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

open-webui open-webui open_webui:open_webui (from the name)	before 0.9.5	CNA record
openwebui open_webui openwebui:open_webui	before 0.9.5	NVD

References

References

https://github.com/open-webui/open-webui/security/advisories/GHSA-4g37-7p2c-38r9	x-refsource-confirm, exploit, mitigation, vendor-advisory
https://github.com/open-webui/open-webui/pull/22109	x-refsource-misc, issue-tracking, patch
https://github.com/open-webui/open-webui/releases/tag/v0.9.5	x-refsource-misc, release-notes

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.