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*Details: File format summary



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Name PKCS #7 Cryptographic Message File
Other names  
Identifiers MIME:  application/pkcs7-mime
MIME:  application/pkcs7-signature
PUID:  fmt/670
Classification Text (Structured)
Description PKCS #7 Cryptographic Message File is a form of electronic signature used to secure messages that can only be read by the intended recipient. PKCS #7 describes a general syntax for data that may have cryptography applied to it, such as digital signatures and digital envelopes. PKCS #7 is one of the family of standards called Public-Key Cryptography Standards (PKCS) devised and published by RSA Security Inc, starting in the early 1990s; storing signed and/or encrypted data, usually attached to an email message that includes an S/MIME (Secure/Multipurpose Internet Mail Extensions) digital signature. The extension .p7s usually refers to PKCS #7 Signature Files; .p7m usually refers to PKCS #7 MIME Files; and .p7b usually refers to PKCS #7 Certificate Files. The research of this format is still ongoing, please contact the PRONOM team if you how any more information regarding this format.
Byte order  
Related file formats Has lower priority than ZFO (Message) File  
Has lower priority than ZFO (Sent Message) File  
Has lower priority than ZFO (Proof of Delivery) File  
Has priority over Extensible Markup Language (1.0)
Technical Environment  
Supported until  
Format Risk  
Developed by None.
Supported by None.
Source Digital Preservation Department / The National Archives
Source date 23 Sep 2014
Source description 11/2023 (v.116)- Priority over fmt/101 added. Internally researched.
Last updated 16 Nov 2023
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