open-webui Open WebUI up to 0.6.43 Response Message cross site scripting

Summaryinfo

A vulnerability was found in open-webui Open WebUI up to 0.6.43. It has been rated as problematic. This issue affects some unknown processing of the component Response Message Handler. The manipulation leads to cross site scripting. This vulnerability is referenced as CVE-2026-26193. Remote exploitation of the attack is possible. No exploit is available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in open-webui Open WebUI up to 0.6.43 and classified as problematic. This issue affects an unknown function of the component Response Message Handler. The manipulation with an unknown input leads to a cross site scripting vulnerability. Using CWE to declare the problem leads to CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. Impacted is integrity. The summary by CVE is:

Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to version 0.6.44, aanually modifying chat history allows setting the `embeds` property on a response message, the content of which is loaded into an iFrame with a sandbox that has `allow-scripts` and `allow-same-origin` set, ignoring the "iframe Sandbox Allow Same Origin" configuration. This enables stored XSS on the affected chat. This also triggers when the chat is in the shared format. The result is a shareable link containing the payload that can be distributed to any other users on the instance. Version 0.6.44 fixes the issue.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2026-26193 since 02/11/2026. The exploitation is known to be easy. The attack may be initiated remotely. It demands that the victim is doing some kind of user interaction. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1059.007 according to MITRE ATT&CK.

Upgrading to version 0.6.44 eliminates this vulnerability.

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

Productinfo

Vendor

• open-webui

Name

• Open WebUI

Version

• 0.6.0
• 0.6.1
• 0.6.2
• 0.6.3
• 0.6.4
• 0.6.5
• 0.6.6
• 0.6.7
• 0.6.8
• 0.6.9
• 0.6.10
• 0.6.11
• 0.6.12
• 0.6.13
• 0.6.14
• 0.6.15
• 0.6.16
• 0.6.17
• 0.6.18
• 0.6.19
• 0.6.20
• 0.6.21
• 0.6.22
• 0.6.23
• 0.6.24
• 0.6.25
• 0.6.26
• 0.6.27
• 0.6.28
• 0.6.29
• 0.6.30
• 0.6.31
• 0.6.32
• 0.6.33
• 0.6.34
• 0.6.35
• 0.6.36
• 0.6.37
• 0.6.38
• 0.6.39
• 0.6.40
• 0.6.41
• 0.6.42
• 0.6.43

CPE 2.3info

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CPE 2.2info

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