Auth bypass in 1panel-Dev Maxkb

CVE-2026-77516

MaxKB is an open-source AI assistant for enterprise. From version 2.0.0 through 2.9.2, a lowest-role workspace member denied access to a tool by WorkspaceUserResourcePermission can still bind its identifier through tool_ids, skill_tool_ids, or mcp_tool_ids and execute it through the agent or workflow dispatch path. The dispatch path does not reapply the per-tool grant enforced by dedicated tool routes, and tool execution decrypts server-side init_params, allowing the caller to receive credentials carried by the denied tool. No fixed version is available as of this review.

Vulnerability class: IDOR (Insecure Direct Object Reference)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.002 (15.4th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 15th percentile — 15.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-77516: held from 0.002 to 0.002.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-77516?
CVE-2026-77516 is a medium-severity vulnerability in 1panel-Dev Maxkb, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 5.4/10. Published 2026-09-21.
How severe is CVE-2026-77516?
Medium severity. CVSS v3 base score is 5.4 out of 10.