This analysis explores the challenges of decoding encrypted PDF documents, particularly in the context of phishing. It explains that while the structure of encrypted PDFs remains visible, strings and streams are encrypted. The article recommends using qpdf, an open-source tool, to decrypt PDFs for further analysis. It demonstrates the process using a phishing PDF example, showing how to determine if a password is required and how to decrypt the document. The importance of decryption prior to using tools like pdf-parser is emphasized, as it allows for the extraction of crucial information such as URIs, which would otherwise appear as ciphertext.