VulnerabilityDeferred

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 9.8EPSS 1.20%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.20%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

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.

CVSS 3.1: 9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS: 1.20% probability · 66th percentile
CISA KEV: Not listed
Weakness: CWE-94
Source: cve@mitre.org

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.