CVE-2022-3358

A flaw was found in OpenSSL, where it incorrectly handles legacy custom ciphers passed to the EVP_EncryptInit_ex2(), EVP_DecryptInit_ex2() and EVP_CipherInit_ex2() functions (as well as other similarly named encryption and decryption initialization functions). Instead of using the custom cipher directly, it incorrectly tries to fetch an equivalent cipher from the available providers. An equivalent cipher is found based on the NID passed to EVP_CIPHER_meth_new(). This NID is supposed to represent the unique NID for a given cipher. However, it is possible for an application to incorrectly pass NID_undef as this value in the call to EVP_CIPHER_meth_new(). When NID_undef is used this way, the OpenSSL encryption/decryption initialization function will match the NULL cipher as equivalent and fetch this from the available providers. This is successful if the default provider has been loaded (or if a third-party provider has been loaded that offers this cipher). Using the NULL cipher means that the plaintext is emitted as the ciphertext.