Open WebUI up to 0.11.3 Chat Fork /api/v1/chats/{id}/fork chat fork handler id improper authorization

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.2$0-$5k2.08

Summaryinfo

A vulnerability classified as critical has been found in Open WebUI up to 0.11.3. Impacted is the function chat fork handler of the file /api/v1/chats/{id}/fork of the component Chat Fork Handler. The manipulation of the argument ID leads to improper authorization. This vulnerability is traded as CVE-2026-109284. It is possible to initiate the attack remotely. There is no exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Open WebUI up to 0.11.3. It has been rated as critical. This issue affects the function chat fork handler of the file /api/v1/chats/{id}/fork of the component Chat Fork Handler. The manipulation of the argument id with an unknown input leads to a improper authorization vulnerability. Using CWE to declare the problem leads to CWE-285. The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

Open WebUI from 0.11.0 before 0.11.4 contains an improper authorization vulnerability in the chat fork handler, which places forked chats in the source chat's folder without checking folder write access. Shared folder members downgraded to read-only can call POST /api/v1/chats/{id}/fork on chats they created there while they had write access, inserting attacker-controlled chats visible to the folder owner and members.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2026-109284 since 10/12/2026. The exploitation is known to be easy. The attack may be initiated remotely. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1548.002 according to MITRE ATT&CK.

Upgrading to version 0.11.4 eliminates this vulnerability.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.2

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

CNA Base Score: 4.3
CNA Vector (VulnCheck): 🔒

CVSSv2info

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

Exploitinginfo

Class: Improper authorization
CWE: CWE-285 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
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 0.11.4

Timelineinfo

10/12/2026 Advisory disclosed
10/12/2026 +0 days CVE reserved
10/12/2026 +0 days VulDB entry created
10/12/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-109284 (🔒)
GCVE (CVE): GCVE-0-2026-109284
GCVE (VulDB): GCVE-100-417059

Entryinfo

Created: 10/12/2026 19:28
Changes: 10/12/2026 19:28 (78)
Complete: 🔍
Cache ID: 216::103

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