open-webui Open WebUI up to 0.8.5 chat_completion tool_ids authorization

CVSS Meta Temp Score
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CTI Interest Score
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6.5$0-$5k0.00

Summaryinfo

A vulnerability has been found in open-webui Open WebUI up to 0.8.5 and classified as critical. Affected is the function chat_completion. This manipulation of the argument tool_ids causes authorization. This vulnerability is tracked as CVE-2026-45350. The attack is possible to be carried out remotely. No exploit exists. The affected component should be upgraded.

Detailsinfo

A vulnerability has been found in open-webui Open WebUI up to 0.8.5 and classified as critical. Affected by this vulnerability is the function chat_completion. The manipulation of the argument tool_ids with an unknown input leads to a authorization vulnerability. The CWE definition for the vulnerability is CWE-862. The product does not perform an authorization check when an actor attempts to access a resource or perform an action. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.8.6, there is a vulnerability in chat completion API, which allows attackers to bypass tool restrictions, potentially enabling unauthorized actions or access. In the chat_completion API, the parameters tool_ids and tool_servers are supplied by the user. These parameters are used to create a tools_dict by the middleware. This is then used by get_tool_by_id to retrieve the appropriate tool. However, there is no checks in that ensures the user that uses the API has permission to use the tool, meaning that a user can invoke any server tool by supplying the correct tool_id or tool_servers parameters via the chat completion API. Moreover, the authentication token stored in the server would be used when invoking the tool, so the tool will be invoked with the server privilege. This vulnerability is fixed in 0.8.6.

The advisory is shared at github.com. This vulnerability is known as CVE-2026-45350 since 05/11/2026. The exploitation appears to be easy. The attack can be launched remotely. Technical details are known, but no exploit is available.

Upgrading to version 0.8.6 eliminates this vulnerability.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.7
VulDB Meta Temp Score: 6.5

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.1
CNA Vector (GitHub_M): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Authorization
CWE: CWE-862 / CWE-863 / CWE-285
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Open WebUI 0.8.6

Timelineinfo

05/11/2026 CVE reserved
05/16/2026 +5 days Advisory disclosed
05/16/2026 +0 days VulDB entry created
05/16/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: GHSA-4pcg-253r-rf9w
Status: Confirmed

CVE: CVE-2026-45350 (🔒)
GCVE (CVE): GCVE-0-2026-45350
GCVE (VulDB): GCVE-100-364297

Entryinfo

Created: 05/16/2026 06:51
Changes: 05/16/2026 06:51 (65)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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