CVE-2026-105797

SimpleChat: Command injection via authorization-gate ordering flaw (arbitrary process spawn through MCP stdio transport)

HIGH
8.8
CVSS Score
Published: October 6, 2026 at 02:23 PM UTC
Updated: October 6, 2026 at 06:16 PM UTC
1 product affected across 1 vendorSimpleChat

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Severity
HIGH8.8
Exploit prediction
EPSS 0.6%
SSVC
PoC

Description

SimpleChat is a secure AI conversation application with personal and group workspaces for document-grounded interactions. In versions 0.261.003 and 0.261.027, an authorization ordering flaw in POST /api/user/plugins allows an authenticated low-privileged user to omit the top-level MCP type so that _reject_non_admin_mcp_stdio skips inspection before the type is restored from metadata. The stored personal action can then reach McpPluginFactory.create_connector, and MCPStdioPlugin.connect starts the attacker-selected operating-system process under the application service identity when the action tool is invoked. Exploitation requires personal plugins to be enabled and governance to permit MCP actions, and it can expose or modify secrets and data available to the service or disrupt the service. This issue is fixed in version 0.261.031.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 0.261.031

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

SSVC — Action Prioritization

SSVCPoCNot automatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

8.8HIGHGitHub_M
Attack Vector
NETWORK
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-78CWE-863

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