CVE-2026-45555: CWE-94: Improper Control of Generation of Code ('Code Injection') in MarcelRoozekrans roslyn-codelens-mcp
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.
AI Analysis
Technical Summary
The roslyn-codelens-mcp server, which provides semantic code intelligence for .NET codebases, contains a code injection vulnerability (CWE-94) in its get_diagnostics MCP tool. Versions from 0.0.9 to 1.17.0 load and execute all DiagnosticAnalyzer assemblies referenced by the target solution without any allowlist, signature check, or user confirmation, with includeAnalyzers defaulting to true. This allows an attacker who can place a malicious .csproj referencing an attacker-controlled DLL in a location opened by the MCP server to execute arbitrary code with the server's OS privileges. The vulnerability is resolved in version 1.17.0.
Potential Impact
Successful exploitation results in arbitrary code execution within the MCP server process, running with the operating system privileges of the server. This can lead to full compromise of the host running the roslyn-codelens-mcp server. The vulnerability requires local or limited access to cause the victim to open a malicious project file. No known exploits in the wild have been reported.
Mitigation Recommendations
Upgrade roslyn-codelens-mcp to version 1.17.0 or later, where this vulnerability is fixed. Since no official patch advisory is provided, verify the upgrade addresses the issue. Until upgraded, avoid opening untrusted .csproj files or solutions with the MCP server to prevent arbitrary code execution. Patch status is not explicitly confirmed beyond the version fix indication; check the vendor's official channels for current remediation guidance.
CVE-2026-45555: CWE-94: Improper Control of Generation of Code ('Code Injection') in MarcelRoozekrans roslyn-codelens-mcp
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.
CVSS v3.1
Score 7.8high
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The roslyn-codelens-mcp server, which provides semantic code intelligence for .NET codebases, contains a code injection vulnerability (CWE-94) in its get_diagnostics MCP tool. Versions from 0.0.9 to 1.17.0 load and execute all DiagnosticAnalyzer assemblies referenced by the target solution without any allowlist, signature check, or user confirmation, with includeAnalyzers defaulting to true. This allows an attacker who can place a malicious .csproj referencing an attacker-controlled DLL in a location opened by the MCP server to execute arbitrary code with the server's OS privileges. The vulnerability is resolved in version 1.17.0.
Potential Impact
Successful exploitation results in arbitrary code execution within the MCP server process, running with the operating system privileges of the server. This can lead to full compromise of the host running the roslyn-codelens-mcp server. The vulnerability requires local or limited access to cause the victim to open a malicious project file. No known exploits in the wild have been reported.
Mitigation Recommendations
Upgrade roslyn-codelens-mcp to version 1.17.0 or later, where this vulnerability is fixed. Since no official patch advisory is provided, verify the upgrade addresses the issue. Until upgraded, avoid opening untrusted .csproj files or solutions with the MCP server to prevent arbitrary code execution. Patch status is not explicitly confirmed beyond the version fix indication; check the vendor's official channels for current remediation guidance.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-05-12T17:48:47.880Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a19993ae29bf47b50eaf566
Added to database: 5/29/2026, 1:48:42 PM
Last enriched: 5/29/2026, 2:04:23 PM
Last updated: 5/31/2026, 4:55:55 AM
Views: 9
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