CVE-2026-77516: MaxKB: Missing per-tool authorization in the agent and workflow tool-dispatch path
Vulnerability summary
CVE-2026-77516 is a medium (CVSS 5.4) vulnerability in 1panel-dev maxkb. EPSS estimates a 0.24% chance of exploitation in the next 30 days, higher than 15.3% of scored vulnerabilities.
Not severe (CVSS 5.4, network access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Timeline
- 21-09-2026PublishedVulnerability first disclosed.
- 28-09-2026Last modifiedVulnerability information updated.
Description
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.
CVSS metrics
2 scores · 2 sources · 1 version- NVDNIST5.4MediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
EPSS trend
Probability
0.24%
Chance of exploitation in the next 30 days
Percentile
15%
Versus all other CVEs
30-day change
No change 0.00 pp
From 0.24% on 04-10-2026
Known exploited
Compare KEV catalogsNot in the CISA KEV catalog.
Not in the ENISA CNW catalog.
Not in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root cause- 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.
Affected systems
Known conditions: network-reachable, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.
1panel-dev1 product
- maxkb≥ 2.0.0, ≤ 2.9.2
1 vendor · 1 product
References
1 links- github.com/1Panel-dev/MaxKB/security/advisories/GHSA-383v-fx78-pphmX Refsource CONFIRM