MarcelRoozekrans roslyn-codelens-mcp up to 1.16.x get_diagnostics code injection

Summaryinfo

A vulnerability classified as critical has been found in MarcelRoozekrans roslyn-codelens-mcp up to 1.16.x. This impacts the function get_diagnostics. Performing a manipulation results in code injection. This vulnerability was named CVE-2026-45555. The attack needs to be approached locally. There is no available exploit. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in MarcelRoozekrans roslyn-codelens-mcp up to 1.16.x. It has been classified as critical. This affects the function get_diagnostics. The manipulation with an unknown input leads to a code injection vulnerability. CWE is classifying the issue as CWE-94. The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

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.

The advisory is shared at github.com. This vulnerability is uniquely identified as CVE-2026-45555 since 05/12/2026. The exploitability is told to be easy. An attack has to be approached locally. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1059 for this issue.

Upgrading to version 1.17.0 eliminates this vulnerability.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

• Artificial Intelligence Software

Vendor

• MarcelRoozekrans

Name

• roslyn-codelens-mcp

Version

• 1.0
• 1.1
• 1.2
• 1.3
• 1.4
• 1.5
• 1.6
• 1.7
• 1.8
• 1.9
• 1.10
• 1.11
• 1.12
• 1.13
• 1.14
• 1.15
• 1.16

Website

• Product: https://github.com/MarcelRoozekrans/roslyn-codelens-mcp/

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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