On Mon, Apr 12, 2021 at 07:23:50PM +0200, richard lucassen wrote: > mail.info: Apr 12 18:01:16 opendkim[13977]: 828FE7F581: s=202103 d=example.com > SSL error:0407008A:rsa routines:RSA_padding_check_PKCS1_type_1:invalid > padding; > error: 04067072:rsa routines:rsa_ossl_public_decrypt:padding check failed
An RSA signature is either slightly garbled, or is being verified with the wrong key (not the one that did the signing). The validator detects a PKCS#1 padding error after decrypting with the public key. I'm inclined to guess wrong key, but minor corruption in the signature value that preserves the overall length is also possible. -- Viktor.