NetSight
high7.8

CVE-2026-45555

Roslyn CodeLens MCP Server is a Roslyn-based MCP server providing semantic code intelligence for .NET codebases.

Impact

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.

Affected packages

This record carries no package version data, so it cannot be matched against a dependency list automatically. Read the advisory and compare your version by hand.

Weakness classification

References