EUVD Vulnerability Catalog

EUVD-2026-77357

Severity: CRITICAL Base Score: 9.8 CVSS Version: 3.1

Vulnerability Description

Bifrost registers MCP clients through its management API. A stdio client is a command plus args. Bifrost starts that program in the gateway the moment the client is added. No MCP handshake required. The default is governance.auth_config.is_enabled=false. Auth off means every caller is a local admin. One unauthenticated POST /api/mcp/client is enough to run a program as the Bifrost process user (appuser on the official image). transports/v2.1.0 refuses an unauthenticated stdio registration with 403. transports/v2.0.0 still allows it.

CVSS Vector Analysis

Below is the complete, human-readable breakdown of the CVSS metric string: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

▪ Attack Vector (AV): Network

▪ Attack Complexity (AC): Low

▪ Privileges Required (PR): None

▪ User Interaction (UI): None

▪ Scope (S): Unchanged

▪ Confidentiality Impact (C): High

▪ Integrity Impact (I): High

▪ Availability Impact (A): High

Affected Vendors & Systems

Vendor maximhq

References & Advisory Links

Metadata Profile

Database Authority

European Union Agency for Cybersecurity (ENISA) EUVD

Assigner

JFROG

EPSS Probability

Known Aliases

CVE-2026-90898

Published On

2026-09-14

Last Updated

2026-09-14