Open WebUI up to 0.11.0 Channel Membership main.py chat_completion authorization

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.2$0-$5k0.00+

Summaryinfo

A vulnerability has been found in Open WebUI up to 0.11.0 and classified as problematic. Impacted is the function chat_completion of the file backend/open_webui/main.py of the component Channel Membership. Performing a manipulation results in authorization. This vulnerability is identified as CVE-2026-87994. The attack can be initiated remotely. There is not any exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Open WebUI up to 0.11.0. It has been classified as problematic. This affects the function chat_completion of the file backend/open_webui/main.py of the component Channel Membership. The manipulation with an unknown input leads to a authorization vulnerability. CWE is classifying the issue as CWE-862. The product does not perform an authorization check when an actor attempts to access a resource or perform an action. This is going to have an impact on integrity. The summary by CVE is:

Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.9.5 until 0.11.1, the channel branch of chat_completion in backend/open_webui/main.py checked channel write access and channel membership for a supplied message_id but did not verify that the calling user authored the targeted message. A channel member could use the chat completions endpoint to replace another member's message while preserving the victim as the stored author, altering the conversation record without gaining access to other channels. This issue is fixed in version 0.11.1.

The advisory is shared at github.com. This vulnerability is uniquely identified as CVE-2026-87994 since 09/09/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. Technical details are known, but no exploit is available.

Upgrading to version 0.11.1 eliminates this vulnerability.

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Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 4.2

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 4.3
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
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 0.11.1

Timelineinfo

09/09/2026 Advisory disclosed
09/09/2026 +0 days CVE reserved
09/09/2026 +0 days VulDB entry created
09/09/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-87994 (🔒)
GCVE (CVE): GCVE-0-2026-87994
GCVE (VulDB): GCVE-100-401901

Entryinfo

Created: 09/09/2026 23:45
Changes: 09/09/2026 23:45 (65)
Complete: 🔍
Cache ID: 216::103

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