Topic: PKCS#7 CMS detached signature verification failure (ASN_PARSE_E)
I try to do a verification of a detached PKCS#7 CMS signature. The verification fails with ASN_PARSE_E (-140). I'm using function wc_PKCS7_VerifySignedData_ex. The reason why it fails is an ASN.1 parsing synchronization error. It happens after the failing attempt to read non-existing signed data (after object 1.2.840.1135188.8.131.52) from the signature. Instead on this position the sequence of certificates begins, but wc_PKCS7_VerifySignedData_ex already returned with ASN_PARSE_E. In my opinion, wc_PKCS7_VerifySignedData_ex should be able to handle both situations. Either there is signed data OR an implicit set of certificates.
Please find attached the binary (its SHA256 was used for signing) and the resulting signature.
I used wolfSSL from https://github.com/wolfSSL/wolfssl commit: c57fee136a40f7dcd2c8315a3c6bfe602ca98b8c