CVE-2026-39425 Details
Description
MaxKB is an open-source AI assistant for enterprise. Versions 2.7.1 and below contain a Stored Cross-Site Scripting (XSS) vulnerability that allows authenticated users to inject arbitrary HTML and JavaScript into the Application prologue (Opening Remarks) field by wrapping malicious payloads in <html_rander> tags. The backend fails to sanitize or encode HTML entities in the prologue field when applications are created or updated via the /admin/api/workspace/{workspace_id}/application endpoint, storing the raw payload directly in the database. The frontend then renders this content using an innerHTML-equivalent mechanism, trusting <html_rander>-wrapped content to be safe, which enables persistent DOM-based Stored XSS execution against any visitor who opens the affected chatbot interface. Exploitation can lead to session hijacking, unauthorized actions performed on behalf of victims (such as deleting workspaces or applications), and sensitive data exposure. This issue has been fixed in version 2.8.0.
A stored cross-site scripting vulnerability has been identified in MaxKB, an open-source AI assistant for enterprise, in versions through 2.7.1. This vulnerability allows authenticated users to inject arbitrary HTML and JavaScript into the Application prologue field by enclosing malicious payloads in <html_rander> tags. The issue arises because the backend does not properly sanitize or encode HTML entities in the prologue when applications are created or updated via the /admin/api/workspace/{workspace_id}/application endpoint. As a result, the raw payload is stored in the database and later rendered on the frontend using an innerHTML-equivalent mechanism, trusting <html_rander>-wrapped content to be safe. This exploitation leads to persistent DOM-based stored XSS execution against any visitor who opens the affected chatbot interface, with potential consequences including session hijacking, unauthorized actions performed on behalf of victims, and exposure of sensitive data.
Users can upgrade to MaxKB version 2.8.0 to address this vulnerability.
Metrics
CVSS 4.0 Severity and Vector Strings:
CVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
CISA-ADP
Assessed Apr 14, 2026References to Advisories, Solutions, and Tools
By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.
| URL | Source(s) | Tag(s) |
|---|---|---|
| https://github.com/1Panel-dev/MaxKB/releases/tag/v2.8.0 | [email protected] | Release Notes |
| https://github.com/1Panel-dev/MaxKB/security/advisories/GHSA-3rq5-pgm7-pvp4 | [email protected] | Vendor Advisory |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-80 | Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS) | [email protected] |
Affected Products
| Product | Versions |
|---|---|
| maxkb maxkb | < 2.8.0 |
CPE
Remediation
| |
Change History
4 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Jun 17, 2026 | CVE Modified | [email protected] |
| Jun 17, 2026 | CVE Modified | CISA-ADP |
| Apr 20, 2026 | Initial Analysis | [email protected] |
| Apr 14, 2026 | New CVE Received | [email protected] |