PDF glossary
PKCS #7 (CMS)
The standard format for signed data used by PDF digital signatures; its current name is Cryptographic Message Syntax (CMS).
A PDF signature stores a PKCS #7 / CMS structure: the signature value, the signer’s certificate and signed attributes such as the signing time. In a “detached” signature, the signed data — the document’s bytes — is not copied into it, only its digest.
In PDF-SDK
Digital signatures are written as detached PKCS #7 (CMS), with SHA-256.
PDF signaturesLast reviewed