CVE-2026-77520: MaxKB: Homepage ranking leaks application IDs that workflow application-nodes can use to invoke another user's application

Vulnerability summary

CVE-2026-77520 is a medium (CVSS 5.4) Missing Authorization 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. 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.

• CWE-862Missing AuthorizationThe product does not perform an authorization check when an actor attempts to access a resource or perform an action.