Feature

Digital signatures for PDF — from a quick mark to real cryptography

Three ways to sign, including a genuine PKCS#7 cryptographic signature that appears in Adobe Reader's Signature Panel and is tamper-evident.

"Signing a PDF" can mean very different things. Pasting a picture of your signature is not the same as a cryptographically verifiable signature that proves a document has not been altered. MayaPDF gives you three signature types so you can match the method to the stakes.

1. Image signature

Draw your signature with a mouse, finger, or stylus; type it; or upload an image of it. MayaPDF places it on the page and flattens it into the PDF. This is quick and familiar — right for low-stakes internal documents where you just need a visible mark.

2. Visual signature block

A formal block showing the signer's name, the date, and a reason ("Approved", "Verified"). It reads like the signature line on an office letter and is useful when you want a clear, human-readable record on the page.

3. Real cryptographic signature (PKCS#7 / PAdES)

This is the one that carries legal and technical weight. MayaPDF embeds an industry-standard PKCS#7 digital signature into the PDF using an incremental update, so the original bytes are preserved and a signature revision is appended. In practice that means:

  • The signature appears in Adobe Reader's Signature Panel.
  • It is tamper-evident: if a single byte of the signed content changes, the signature breaks and the reader flags it.
  • It follows the same PAdES-style approach used for compliant PDF signing.

You can also combine a visible signature block with the invisible cryptographic signature, so the document both looks signed and is verifiably signed.

What "validity unknown" means (an honest note)

During the free trial you can generate a self-signed certificate inside MayaPDF and sign with it. When a recipient opens such a PDF, Adobe Reader will show the signature as "validity unknown" until they choose to trust your certificate. This is normal, expected behaviour for any self-signed certificate — it does not mean the signature is broken; it means the reader has not yet been told to trust that particular issuer. The signature is still cryptographically valid and tamper-evident.

Use your own DSC / PFX certificate (MayaPDF Pro)

If you have a Digital Signature Certificate (DSC) from a licensed Indian Certifying Authority, or any PFX/.p12 certificate, MayaPDF Pro lets you upload it and sign with it. That produces a signature backed by a recognised certificate, which is what you need for legally consequential documents. This is a Pro feature (₹999/year) — the strongest and most honest reason to upgrade: anyone who needs a legally usable signature should use their own certificate.

Your security matters here: certificate private keys generated in-app are stored encrypted with AES-256-GCM, and a PFX password you type is used in memory only — never stored or logged.

Legal recognition in India

Electronic records and electronic signatures are recognised under India's Information Technology Act, 2000. Whether a specific document can be signed electronically depends on its type and the applicable rules; some instruments still require other formalities. MayaPDF gives you the technical tools; the appropriateness for a given document is your call.

Start signing free See Pro (₹999/yr)