CVE-2026-77517: MaxKB cross-knowledge IDOR lets a normal user read and modify documents and paragraphs in another knowledge base

Vulnerability summary

CVE-2026-77517 is a medium (CVSS 5.4) vulnerability in 1panel-dev maxkb. EPSS estimates a 0.23% chance of exploitation in the next 30 days, higher than 13.9% of scored vulnerabilities.

Timeline

1. 21-09-2026
   PublishedVulnerability first disclosed.
2. 22-09-2026
   Last modifiedVulnerability information updated.

Description

MaxKB is an open-source AI assistant for enterprise. From version 2.0.0 through 2.10.2-lts, document and paragraph operate routes authorize only knowledge_id in the request path, then query the target Document by document_id or Paragraph by paragraph_id without confirming that the object belongs to that knowledge base. A normal workspace user with a known victim document or paragraph UUID can use an attacker-owned knowledge-base path to read or modify content in another user's knowledge base. No fixed version is available as of this review.

• CWE-639Authorization Bypass Through User-Controlled KeyThe system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data.
• CWE-862Missing AuthorizationThe product does not perform an authorization check when an actor attempts to access a resource or perform an action.