VerifySigned return false

I tested a partially signed pdf file and found that VerifySigned would return false, not sure if it was correct.

@Feng_Minxuan

Would you kindly explain what you mean by partially signed PDF? Also, please share the sample file with us so that we can test the scenario in our environment and address it accordingly.

Thank you for the reply.
partiallySigned.pdf (1.1 MB)
I combine two PDF files, one of which is a signed PDF file.

using (var signature = new PdfFileSignature(document))
{
var sigNames = signature.GetSignNames();
if ((sigNames.Count > 0) && signature.VerifySigned(sigNames[0] as string) && signature.ContainsSignature())
{
return true;
}
}

@Feng_Minxuan

We were able to reproduce the issue in our environment. The verification of partial signatures needs more investigation and for the sake, we have logged an investigation ticket as PDFNET-48248 in our issue tracking system. We will further look into its details and keep you posted with the status of its resolution. Please be patient and spare us some time.

We are sorry for the inconvenience.

@Feng_Minxuan

We have been investigating the earlier logged ticket. Can you please share how the documents were merged? If the document was merged - VerifySigned must return false, because the document has been modified. Merging is modifying too.