CVE Catalog

CVE-2026-39424

MediumCVSS 4.7
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.37%

31th percentile - higher than 31% of all known CVEs

Summary

MaxKB versions 2.7.1 and below are vulnerable to Improper Neutralization of Formula Elements in a CSV File. When an administrator exports chat history to an Excel file (.xlsx), strings starting with formula characters are written without proper sanitization, which can lead to Arbitrary Code Execution (RCE) on the administrator's workstation via Dynamic Data Exchange (DDE) when opened in spreadsheet applications like Microsoft Excel.

Risk Assessment

An administrator opening the exported Excel file could execute malicious formulas, leading to remote code execution on their workstation and potential compromise.

Recommendation

Upgrade MaxKB to version 2.8.0 or later. Until then, avoid opening exported Excel files from untrusted sources or apply additional sanitization.

Other vulnerabilities in MaxKB

See all
Original NVD description (English source)

MaxKB is an open-source AI assistant for enterprise. In versions 2.7.1 and below, the chat export feature is vulnerable to Improper Neutralization of Formula Elements in a CSV File. When an administrator exports the application chat history to an Excel file (.xlsx) via the /admin/api/workspace/{workspace_id}/application/{application_id}/chat/export endpoint, strings starting with formula characters are written directly without proper sanitization. Opening this file in spreadsheet applications like Microsoft Excel can lead to Arbitrary Code Execution (RCE) on the administrator's workstation via Dynamic Data Exchange (DDE). The issue is a variant of CVE-2025-4546, which fixed the exact same pattern in apps/dataset/serializers/document_serializers.py but missed the application chat export sink. This issue has been fixed in version 2.8.0.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS