Software
The AssinaJá Certificados application lets you sign documents in AssinaJá with the digital certificate you already have — installed on your computer, in a .p12 or .pfx file, or on a card. It is available for Windows, macOS and Linux and installs in a few minutes.
AssinaJá Certificados
The application is a small program that works together with the browser extension of the same name. It finds the certificates installed on your computer, shows a confirmation window before each signature and signs — without the certificate's key ever leaving your computer.
You only need it to sign with a Local Digital Certificate. To sign with the Digital Mobile Key (Chave Móvel Digital, CMD) or with a drawn signature, you do not need to install anything.
- Signs with the digital certificate of the Ordem dos Advogados (Portuguese Bar Association) and with other certificates from recognised certification authorities
- Reads the certificates installed in Windows (including those on cards connected to the computer) and in the macOS Keychain, and .p12 or .pfx files on any system
- Works in Google Chrome, Microsoft Edge and Mozilla Firefox
- On Windows it installs for your user only, with no administrator password
Why an application is needed
Browsers do not give web pages access to the certificates installed on your computer. It is a security decision by the browsers themselves — and it is why, until now, signing a PDF with the Bar Association certificate meant using Acrobat.
The application bridges that gap without opening the door to anything else: it receives from AssinaJá only the cryptographic digest of the document, asks you to confirm in its own window and returns the signature. The document never passes through the application.
Supported systems
The application is available for Windows, macOS and Linux. On Linux it signs with certificates in a file (.p12 or .pfx); cards are not yet supported on that system.
| System | Installer | Requirements |
|---|---|---|
| Windows | Available (.msi) | Windows 10 or later, 64-bit (x64) |
| macOS | Available (.pkg) | macOS 14 (Sonoma) or later, Apple Silicon or Intel |
| Linux | Available (.deb and .rpm) | 64-bit (x64); Ubuntu 22.04, Debian 12, Fedora or later; certificates in a .p12/.pfx file |
How to install on Windows
Installation takes three steps and does not ask for an administrator password. The full guide, with every screen and what to do if something fails, is in the help centre.
- Download the Windows installer (.msi) from this page and open it
- Install the AssinaJá Certificados extension in your browser
- Click the extension icon and check that it says “AssinaJá application connected”
See the step-by-step Windows installation guide in the help centre
How to install on macOS
The installer is for all users of the Mac and asks for the administrator password. In this first version it is not yet notarised by Apple: the first time you open it, macOS will refuse it.
- Download the macOS installer (.pkg) from this page and open it
- If macOS says it cannot verify the developer, open System Settings → Privacy & Security and click «Open Anyway»
- Install the AssinaJá Certificados extension in your browser and check on the extension icon that it says “AssinaJá application connected”
- To uninstall, in Terminal: sudo "/Library/Application Support/AssinaJa/WebId/uninstall.sh"
See the step-by-step macOS installation guide in the help centre
How to install on Linux
There is a .deb package for Ubuntu and Debian and an .rpm for Fedora and Red Hat. The package manager also installs what the application needs (OpenSSL and zenity, for the confirmation windows).
- Download the package for your distribution from this page
- Install it: sudo apt install ./assinaja-webid-linux-x64.deb (Ubuntu, Debian) or sudo dnf install ./assinaja-webid-linux-x64.rpm (Fedora, Red Hat)
- Use Chrome, Edge or Firefox from the official packages — the Snap or Flatpak versions may not find the application
- Install the AssinaJá Certificados extension and check on the extension icon that it says “AssinaJá application connected”
See the step-by-step Linux installation guide in the help centre
Security
The application is designed so that no website, not even a compromised page, can sign on your behalf without you noticing.
- The certificate's key never leaves the computer
- The file password or the card PIN is only asked for in an application window, never on the web page
- It only signs requests coming from AssinaJá — requests from other sites are refused
- Before each signature it shows the site requesting it, the document and the certificate, with Cancel selected by default
- The signature produced is an Advanced Electronic Signature, checked by AssinaJá for the certification chain and revocation