IText broke Specification: ISO 19005-3:2012, Clause: 6.6.2.3, Test number: 7

Question

I'm trying to sign with IText 8 a PDF a PDF/A-3B document. My code seem to work, but I didn't succeed with online validator. The error I get with various site is:

Specification: ISO 19005-3:2012, Clause: 6.6.2.3, Test number: 7
All properties specified in XMP form shall use either the predefined schemas defined in the XMP Specification, ISO 19005-1 or this part of ISO 19005, or any extension schemas that comply with 6.6.2.3.2. Failed 1 occurrences Hide XMPProperty (isPredefinedInXMP2005 == true || isDefinedInMainPackage == true || isDefinedInCurrentPackage == true) && isValueTypeCorrect == true
root/document[0]/metadata[0](23 0 obj PDMetadata)/XMPPackage[0]/Properties[7](http://ns.adobe.com/pdf/1.3/ - pdf:Trapped)

The original document was validated from VerPDF's site meanwhile the result pdf with or without the signin process fail in this way.

My simple code without sign

PdfDocument pdfDoc = new PdfDocument(new PdfReader(pdfInputFileName), new PdfWriter(pdfOutputFileName));
pdfDoc.close()

The original file

The output

The output is without Signature for privacy reason

Any thoughts? Thanks in advance

I've tryied to add writer xmpMetadata but no changes in the result

Answer 1

I believe this is a bug in VeraPDF. The reason why the check fails is that iText (correctly, as far as I'm aware) copies the value of the Trapped entry in the input PDF's info dict into the pdf:Trapped XMP property when rewriting the file, but pdf:Trapped is not in this namespace listing in VeraPDF: https://github.com/veraPDF/veraPDF-library/blob/153e1723da4ea20176b4efe65e176e11e5[…]ore/src/main/java/org/verapdf/model/tools/xmp/XMPConstants.java. AFAIK it should be in there, though (reference: https://developer.adobe.com/xmp/docs/XMPNamespaces/pdf/).

This also has implications for files that claim conformance with both PDF/X-4 and PDF/A-2 or PDF/A-3, since the pdf:Trapped property is mandatory in such files.