CVE-2026-105797 (GCVE-0-2026-105797)

Vulnerability from cvelistv5 – Published: 2026-10-06 14:23 – Updated: 2026-10-06 17:36
VLAI
Title
SimpleChat: Command injection via authorization-gate ordering flaw (arbitrary process spawn through MCP stdio transport)
Summary
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.
Severity
8.8 (High)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: poc Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-06 17:36 UTC
CWE
  • CWE-78 - Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
  • CWE-863 - Incorrect Authorization
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7595 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
microsoft simplechat Affected: < 0.261.031
guessed Create a notification for this product.
Show details on NVD website
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