Thanks for your inquiry. Sure, please try using the following code snippet:
Document doc = new Document(MyDir + "Rendering.doc");
PdfSaveOptions saveOptions = new PdfSaveOptions();
// Create encryption details and set owner password.
PdfEncryptionDetails encryptionDetails = new PdfEncryptionDetails(string.Empty, "password", PdfEncryptionAlgorithm.RC4_128);
// Start by disallowing all permissions.
encryptionDetails.Permissions = PdfPermissions.DisallowAll;
saveOptions.EncryptionDetails = encryptionDetails;
// Render the document to PDF format with the specified permissions.
doc.Save(MyDir + "Rendering.SpecifyPermissions Out.pdf", saveOptions);