Nessus MCP Server

Instructions

Implementation Reference

• src/tools/vulnerabilities.ts:139-208 (handler)

  The main handler function implementing the search_vulnerabilities tool. Validates keyword input, searches through mock vulnerabilities data by name or description, formats and returns matching results or error messages.

  export const searchVulnerabilitiesToolHandler = async (args: Record<string, unknown>) => {
    try {
      // Validate arguments
      if (!args.keyword || typeof args.keyword !== 'string') {
        return {
          content: [
            {
              type: 'text',
              text: 'Error: Keyword is required and must be a string'
            }
          ],
          isError: true
        };
      }
  
      const keyword = args.keyword.toLowerCase();
  
      // Import vulnerabilities from mock-data
      const { vulnerabilities } = await import('../mock-data.js');
  
      // Search for vulnerabilities matching the keyword
      const matches = vulnerabilities.filter(vuln =>
        vuln.name.toLowerCase().includes(keyword) ||
        vuln.description.toLowerCase().includes(keyword)
      );
  
      if (matches.length === 0) {
        return {
          content: [
            {
              type: 'text',
              text: `No vulnerabilities found matching "${args.keyword}"`
            }
          ]
        };
      }
  
      // Format the search results
      let results = `# Vulnerability Search Results for "${args.keyword}"\n\n`;
      results += `Found ${matches.length} matching vulnerabilities:\n\n`;
  
      matches.forEach((vuln, index) => {
        results += `## ${index + 1}. ${vuln.name} (${vuln.id})\n\n`;
        results += `**Severity:** ${vuln.severity.toUpperCase()}\n`;
        results += `**CVSS Score:** ${vuln.cvss_score}\n\n`;
        results += `${vuln.description}\n\n`;
        results += `To get full details, use the \`get_vulnerability_details\` tool with vulnerability_id: ${vuln.id}\n\n`;
      });
  
      return {
        content: [
          {
            type: 'text',
            text: results
          }
        ]
      };
    } catch (error) {
      const mcpError = handleNessusApiError(error);
      return {
        content: [
          {
            type: 'text',
            text: `Error: ${mcpError.message}`
          }
        ],
        isError: true
      };
    }
  };

• src/tools/vulnerabilities.ts:124-137 (schema)

  Defines the input schema for the search_vulnerabilities tool, specifying a required 'keyword' string parameter.

  export const searchVulnerabilitiesToolSchema = {
    name: 'search_vulnerabilities',
    description: 'Search for vulnerabilities by keyword',
    inputSchema: {
      type: 'object',
      properties: {
        keyword: {
          type: 'string',
          description: 'Keyword to search for in vulnerability names and descriptions'
        }
      },
      required: ['keyword']
    }
  };

• src/index.ts:71-86 (registration)

  Registers the search_vulnerabilities tool schema in the ListToolsRequest handler, making it discoverable.

  server.setRequestHandler(
    ListToolsRequestSchema,
    async () => {
      return {
        tools: [
          listScanTemplatesToolSchema,
          startScanToolSchema,
          getScanStatusToolSchema,
          getScanResultsToolSchema,
          listScansToolSchema,
          getVulnerabilityDetailsToolSchema,
          searchVulnerabilitiesToolSchema
        ]
      };
    }
  );

• src/index.ts:109-110 (registration)

  Dispatches calls to the 'search_vulnerabilities' tool by invoking its handler in the CallToolRequest switch statement.

  case 'search_vulnerabilities':
    return await searchVulnerabilitiesToolHandler(args);

• src/index.ts:33-37 (registration)

  Imports the schema and handler for search_vulnerabilities from vulnerabilities.ts for use in the main server.

    getVulnerabilityDetailsToolSchema,
    getVulnerabilityDetailsToolHandler,
    searchVulnerabilitiesToolSchema,
    searchVulnerabilitiesToolHandler
  } from './tools/vulnerabilities.js';