CVE-2026-30618

xszyou Fay 4.3.1 contains a remote code execution vulnerability in its MCP STDIO server management and command execution handling

Critical · published July 15, 2026

CVSS v3.1
9.8
EPSS
1%
Percentile
67.9
In the wild
Unconfirmed
What it is

xszyou Fay 4.3.1 contains a remote code execution vulnerability in its MCP STDIO server management and command execution handling. A remote attacker can access the publicly exposed MCP management interface and configure an MCP STDIO server with attacker-controlled commands and parameters, resulting in execution of arbitrary commands on the server. Successful exploitation allows arbitrary command execution within the context of the Fay service.

The record
Technical detail
CVSS v3.1
9.8 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.01198 · 67.9th percentile
Published
2026-07-15T00:00Z
EPSS history
Timeline
  • 15 JUL 00:00Z
    xszyou Fay 4.3.1 contains a remote code execution vulnerability in its MCP STDIO server management and command execution handling
    cvelistv5