PT-2026-28385 · Unknown · Open-Webui

Scaumacktiv · Published 2026-03-26 · Updated 2026-03-27 · CVE-2026-29070

Positive Technologies (AI Summary)

CVSS v3.1

8.1

High

Base vector

AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H

Name of the Vulnerable Software and Affected Versions Open WebUI versions prior to 0.8.6

Description Open WebUI is an artificial intelligence platform designed for offline operation. A missing access control check when deleting files from a knowledge base allows a user with write access to a knowledge base (or an administrator) to delete arbitrary files from any knowledge base, provided they know the file ID. The issue stems from a lack of validation that the file being deleted actually belongs to the knowledge base the user has access to. The vulnerable code is located in the /api/v1/knowledge/{id}/file/remove API endpoint, specifically within the remove file from knowledge by id function. The file id parameter, form data.file id, is not validated against the current knowledge base. A proof of concept demonstrates an attacker deleting a file from a victim's knowledge base by submitting a request to their own collection with the victim's file ID.

Recommendations Update Open WebUI to version 0.8.6 or later.

Exploit

Fix

Missing Authorization

Weakness Enumeration

CWE-862

Related Identifiers

CVE-2026-29070

GHSA-26GM-93RW-CCHF

Affected Products

Open-Webui

References · 8

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/29xxx/CVE-2026-29070.json · Exploit
• https://github.com/open-webui/open-webui/security/advisories/GHSA-26gm-93rw-cchf · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-29070 · Security Note
• https://osv.dev/vulnerability/CVE-2026-29070 · Vendor Advisory
• https://osv.dev/vulnerability/GHSA-26gm-93rw-cchf · Vendor Advisory
• https://github.com/open-webui/open-webui · Note
• https://github.com/open-webui/open-webui/blob/main/backend/open_webui/routers/knowledge.py#L803 · Note
• https://twitter.com/CVEnew/status/2037513402210288086 · Twitter Post