[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"howto:p7s:linux:en":3},{"resolvedFromAlias":4,"canonicalExt":5,"ext":5,"name":6,"category":7,"categoryName":8,"updatedAt":9,"os":10,"osLabel":11,"quickSolution":12,"stepByStep":13,"recommendedSoftware":16,"alternativeMethods":17,"commonIssues":18,"securityNote":39,"extensionPath":40,"extensionLabel":41,"breadcrumbs":42,"metaDescription":52},false,"p7s","PKCS #7 / S/MIME Digital Signature (detached signature)","certificates","Certificates","2026-06-12T09:20:59.265Z","linux","Linux","To open .P7S files on Linux, if the .p7s belongs to a signed email, open the message in an email client that supports S/MIME signing and verification.",[14,15],"If the .p7s belongs to a signed email, open the message in an email client that supports S/MIME signing and verification.","Use OpenSSL’s pkcs7 command-line tooling to inspect the PKCS #7 signature object and (when you have the original data) verify it.",[],[],[19,26,33],{"title":20,"description":21,"steps":22},"“It won’t open” or looks like a meaningless attachment","A .p7s file is usually a detached signature, not the actual message or document. Double-clicking it may not display anything useful because it’s meant to be verified against the original signed data.",[23,24,25],"Find the original signed content (often the email body and/or the original attachment) that the .p7s corresponds to.","Open the email in an S/MIME-capable mail client so it can automatically associate the signature with the message and show verification status.","If you only have the .p7s file, use OpenSSL to inspect the PKCS #7 structure (you may not be able to verify without the original data).",{"title":27,"description":28,"steps":29},"Signature verification fails or shows as “untrusted”","Verification can fail if the signed content doesn’t exactly match what was signed, or if the signer’s certificate chain is missing/untrusted in your environment.",[30,31,32],"Confirm you are verifying the signature against the exact original content (even minor changes can break validation).","Check whether your software trusts the signer’s certificate chain (for S/MIME, the signer’s certificate and issuing chain typically must be available and trusted).","Use OpenSSL tools to examine the included certificates and signature details to help diagnose chain and trust issues.",{"title":34,"description":35,"steps":36},"Confusion with .p7m (encrypted) vs .p7s (signature)","PKCS #7 is used for multiple message types. In S/MIME, .p7s is specifically for signed-only signature objects, while other PKCS #7 files may represent encrypted data or combined structures.",[37,38],"Check the extension and context: .p7s commonly indicates a signature object for S/MIME signed-only parts.","If you expected encrypted content, look for a different S/MIME/PKCS #7 object (such as a file used for enveloped/encrypted data) rather than a detached signature.","A .p7s file is a signature container; it is usually safe to treat as data, but its purpose is to influence trust decisions (who signed what). Only treat a message as authentic after successful signature verification and certificate trust validation.","/file-extension/p7s",".P7S",[43,46,49],{"label":44,"to":45},"Home","/",{"label":47,"to":48},"How To","/file-extension",{"label":50,"to":51},"Open .P7S on Linux","/how-to/open-p7s-on-linux","Learn how to open .P7S files on Linux with step-by-step instructions, recommended software, and troubleshooting tips."]