libssl3t64: OpenSSL supports creating a custom cipher via the legacyEVP_CIPHER_meth_new() function and associated function calls

OpenSSL supports creating a custom cipher via the legacyEVP_CIPHER_meth_new() function and associated function calls. This functionwas deprecated in OpenSSL 3.0 and application authors are insteadencouraged to use the new provider mechanism in order to implement customciphers. OpenSSL versions 3.0.0 to 3.0.5 incorrectly handle legacy customciphers passed to the EVP_EncryptInit_ex2(), EVP_DecryptInit_ex2() andEVP_CipherInit_ex2() functions (as well as other similarly named encryptionand decryption initialisation functions). Instead of using the customcipher directly it incorrectly tries to fetch an equivalent cipher from theavailable providers. An equivalent cipher is found based on the NID passedto EVP_CIPHER_meth_new(). This NID is supposed to represent the unique NIDfor a given cipher. However it is possible for an application toincorrectly pass NID_undef as this value in the call toEVP_CIPHER_meth_new(). When NID_undef is used in this way the OpenSSLencryption/decryption initialisation function will match the NULL cipher asbeing equivalent and will fetch this from the available providers. Thiswill succeed if the default provider has been loaded (or if a third partyprovider has been loaded that offers this cipher). Using the NULL ciphermeans that the plaintext is emitted as the ciphertext. Applications areonly affected by this issue if they call EVP_CIPHER_meth_new() usingNID_undef and subsequently use it in a call to an encryption/decryptioninitialisation function. Applications that only use SSL/TLS are notimpacted by this issue. Fixed in OpenSSL 3.0.6 (Affected 3.0.0-3.0.5).

Where it's fixed