CVE-2026-39426

MaxKB is an open-source AI assistant for enterprise. Versions 2.7.1 and below contain a Stored Cross-Site Scripting (XSS) vulnerability where the frontend's MdRenderer.vue component parses custom <iframe_render> tags from LLM responses or Application Prologue configurations, bypassing standard Markdown sanitization and XSS filtering. The unsanitized HTML content is passed to the IframeRender.vue component, which renders it directly into an <iframe> via the srcdoc attribute configured with sandbox="allow-scripts allow-same-origin". This can be a dangerous combination, allowing injected scripts to escape the iframe and execute JavaScript in the parent window using window.parent. Since the Prologue is rendered for any user visiting an application's chat interface, this results in a high-impact Stored XSS that can lead to session hijacking, unauthorized actions, and sensitive data exposure. This issue has been fixed in version 2.8.0.

CVSS v3 5.4 MEDIUM

5.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.3 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/1Panel-dev/MaxKB/releases/tag/v2.8.0	Release Notes
https://github.com/1Panel-dev/MaxKB/security/advisories/GHSA-q2qg-43vq-f2wv	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:maxkb:maxkb:*:*:*:*:-:*:*:*

History

No history.

Information

Published : 2026-04-14 02:16

Updated : 2026-06-17 10:42

NVD link : CVE-2026-39426

Mitre link : CVE-2026-39426

CVE.ORG link : CVE-2026-39426

JSON object : View

Products Affected

maxkb

maxkb

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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