CVE-2026-77520

Overview

MaxKB 2.10.2-lts and earlier allow a normal user to retrieve another user's application_id via the question-ranking endpoint, enabling the attacker to trigger workflows that generate and store output under the victim's application. This flaw exposes sensitive identifiers and allows creation of chat records without proper authorization. It affects all users within the same workspace who can publish workflow applications.

Description

MaxKB is an open-source AI assistant for enterprise. In 2.10.2-lts and earlier, a normal user in the same workspace can obtain another user's application_id from the homepage application question-ranking endpoint when the published victim application has ranking activity in the selected date range and the attacker knows or guesses its name, even though direct application detail and debug-open routes deny access. An attacker who can create and publish a workflow application can place the disclosed identifier in an attacker-owned workflow application-node, trigger that workflow, receive output generated by the victim application, and create durable application_chat and application_chat_record rows under the victim application because save and runtime paths do not verify permission to use the referenced application. No fixed version is available as of this review.

Impact

Confidentiality is compromised as attackers can learn application identifiers and generate victim output. Integrity is at risk because attackers can create chat records that appear to originate from the victim. The primary impact is on workspace users and administrators who rely on data isolation.

Remediation

Apply the latest MaxKB release once available; until then, restrict access to the question-ranking endpoint to administrators only, enforce permission checks on application_id exposure, validate user permissions before executing workflows, and audit workflow triggers for unauthorized activity. Disable or secure the workflow creation feature for untrusted users and monitor for anomalous chat record creation.

Risk context

The CVSS v3 score of 5.4 indicates medium severity. No EPSS data is available, but the flaw can lead to data leakage and unauthorized data generation, warranting moderate vigilance.

Affected products

• MaxKB 2.10.2-lts
• MaxKB 2.10.2