Roslyn CodeLens MCP Server is a Roslyn-based MCP server providing semantic code intelligence for .NET codebases. From 0.0.9 to 1.17.0, the get_diagnostics MCP tool loads and executes all DiagnosticAnalyzer assemblies referenced by the target solution without any allowlist, signature check, or user confirmation; includeAnalyzers defaults to true, so no explicit opt-in is required. An attacker who can place a malicious .csproj referencing an attacker-controlled DLL in a location the victim opens with the MCP server will achieve arbitrary code execution in the server process with the server's OS privileges. This vulnerability is fixed in 1.17.0.

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History

Fri, 29 May 2026 17:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Fri, 29 May 2026 16:00:00 +0000

Type Values Removed Values Added
First Time appeared Marcelroozekrans
Marcelroozekrans roslyn-codelens-mcp
Vendors & Products Marcelroozekrans
Marcelroozekrans roslyn-codelens-mcp

Fri, 29 May 2026 13:45:00 +0000

Type Values Removed Values Added
Description Roslyn CodeLens MCP Server is a Roslyn-based MCP server providing semantic code intelligence for .NET codebases. From 0.0.9 to 1.17.0, the get_diagnostics MCP tool loads and executes all DiagnosticAnalyzer assemblies referenced by the target solution without any allowlist, signature check, or user confirmation; includeAnalyzers defaults to true, so no explicit opt-in is required. An attacker who can place a malicious .csproj referencing an attacker-controlled DLL in a location the victim opens with the MCP server will achieve arbitrary code execution in the server process with the server's OS privileges. This vulnerability is fixed in 1.17.0.
Title Roslyn CodeLens MCP Server: Untrusted Roslyn Analyzer Execution via get_diagnostics Leads to Arbitrary Code Execution
Weaknesses CWE-94
References
Metrics cvssV3_1

{'score': 7.8, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H'}


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cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-05-29T16:23:08.979Z

Reserved: 2026-05-12T17:48:47.880Z

Link: CVE-2026-45555

cve-icon Vulnrichment

Updated: 2026-05-29T16:22:27.221Z

cve-icon NVD

Status : Received

Published: 2026-05-29T14:16:30.113

Modified: 2026-05-29T14:16:30.113

Link: CVE-2026-45555

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-05-29T15:46:32Z

Weaknesses