Cannot handle PDF with valid signature (sha256withrsaencryption)

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const verifyPDF = require("@ninja-labs/verify-pdf");
const { verified, authenticity, integrity, expired, signatures } =  verifyPDF(buffer);
{
  verified: false,
  authenticity: undefined,
  integrity: undefined,
  expired: undefined,
  signatures: undefined
} 

The PDF, when opened with LibreOffice or Adobe Acrobat, is shown to have "valid signature".
After digging in, the PDF was signed using algorithm: "sha256withrsaencryption". I'm unable to find much info about it. Is it something the lib could handle in the future?