Security Guide · 14 April 2026

Document Security
Best Practices for eSignatures

Your documents contain sensitive business information. This guide covers the security layers that protect them -- from encryption and authentication to audit trails and data residency.

Why Document Security Matters More Than Ever

In 2025, the average cost of a data breach in Australia reached $4.26 million. For businesses handling contracts, agreements, and legal documents, a security incident does not just cost money -- it destroys trust and can create legal liability.

Ironically, electronic signatures are often more secure than traditional paper processes. A paper document can be photocopied, forged, or lost. An electronically signed document has encryption, an audit trail, and tamper evidence that paper simply cannot match.

But not all eSignature platforms are equal. The security of your documents depends on the practices of the platform you choose. Here is what to look for.

Six Layers of Document Security

Encryption

In Transit and At Rest

Every byte of data is encrypted. TLS 1.3 protects data moving between your browser and our servers. AES-256 encrypts data stored on our infrastructure. Even our internal team cannot read your documents.

TLS 1.3 for all API and web traffic
AES-256 encryption for stored documents
Digital certificates on signed documents
HSTS headers enforcing HTTPS-only access

Authentication

Multi-Factor & OAuth

Strong authentication prevents unauthorised access. SignAndGo supports email/password, Google OAuth, and Microsoft OAuth. Two-factor authentication adds a second layer of verification.

Two-factor authentication (2FA) available
OAuth 2.0 with CSRF state parameter
JWT tokens with secure expiration
Brute-force protection with rate limiting

Audit Trails

Complete Evidence Chain

Every action on every document is recorded with timestamps, IP addresses, user agent strings, and geolocation. This creates a tamper-evident chain of evidence that exceeds the reliability of wet signatures.

Timestamp on every action (open, view, sign)
IP address and geolocation recording
Device and browser identification
Tamper-evident audit certificates

Application Security

Defence in Depth

Beyond encryption and authentication, SignAndGo applies multiple layers of application security to prevent exploitation, injection attacks, and data leakage.

SSRF protection on webhook delivery
Input sanitisation on all user data
Filename sanitisation on uploads
HTML escaping in email templates

Data Residency

Australian Sovereignty

All data is stored in Sydney, Australia (Google Cloud australia-southeast1). This is not a promise -- it is an infrastructure constraint. Our services are pinned to the Sydney region.

All infrastructure in australia-southeast1
No cross-region data replication
Meets Australian Privacy Principles
Suitable for government and healthcare

Access Controls

Least Privilege

Users only see documents they are authorised to access. Business accounts have role-based access control. API keys use scoped permissions (read, write, sign, admin).

Role-based access control (RBAC)
Scoped API keys with minimal permissions
Signed download URLs with expiration
Session timeout on inactivity

Questions to Ask Any eSignature Provider

Before trusting a platform with your sensitive documents, ask these questions.

Where is my data stored? Can you guarantee it stays in my jurisdiction?

What encryption is used in transit and at rest?

Do you support two-factor authentication?

What information does the audit trail capture?

How do you protect against server-side request forgery (SSRF)?

What happens to my data if I cancel my subscription?

Do you have a vulnerability disclosure or bug bounty program?

How are API keys scoped and managed?

What certifications or compliance frameworks do you follow?

How quickly can you respond to a security incident?

Compliance and Regulatory Considerations

Australian Privacy Principles (APP)

The APPs under the Privacy Act 1988 regulate how personal information is handled. Data residency in Australia simplifies compliance with APP 8 (cross-border disclosure) and APP 11 (security of personal information).

Electronic Transactions Act 1999

This Act and its state equivalents give electronic signatures legal validity. The security of your signing process strengthens the evidentiary weight of your signed documents.

Industry-Specific Requirements

Financial services (APRA), healthcare, government, and legal sectors have additional data handling requirements. Australian data residency and strong audit trails help meet these sector-specific obligations.

Notifiable Data Breaches (NDB)

The NDB scheme requires organisations to notify affected individuals and the OAIC of eligible data breaches. Strong encryption and access controls reduce both the likelihood and impact of breaches.

Your Security Responsibilities

A secure platform is only part of the equation. Here is what you should do on your end to maximise document security.

Enable two-factor authentication

Protect your account with 2FA. Even if your password is compromised, 2FA prevents unauthorised access.

Use strong, unique passwords

Use a password manager and generate unique passwords for every service. Never reuse passwords across platforms.

Review access regularly

For business accounts, review who has access and remove users who no longer need it. Apply the principle of least privilege.

Be cautious with API keys

Scope API keys to the minimum permissions needed. Rotate keys regularly and never commit them to version control.

Verify signer identities

Use the correct email addresses for signers. For high-value documents, consider requiring additional identity verification.

Frequently Asked Questions

How are electronic signatures encrypted?

SignAndGo uses TLS 1.3 encryption for all data in transit and AES-256 encryption for data at rest. Signed documents are sealed with a digital certificate that makes any post-signing tampering detectable. This exceeds the encryption standards used by most traditional document handling processes.

What is an audit trail and why does it matter for document security?

An audit trail is a detailed record of every action taken on a document — who opened it, when they signed, their IP address, device information, and geolocation. This creates an evidence chain that is admissible in Australian courts and far more reliable than the evidence available for traditional wet signatures.

Where is my signing data stored?

SignAndGo stores all data in Google Cloud's Sydney (australia-southeast1) region. Documents, signatures, audit trails, and user data never leave Australia. This meets Australian Privacy Principles and data sovereignty requirements for government, healthcare, legal, and financial services.

How does SignAndGo prevent SSRF and other server-side attacks?

SignAndGo implements SSRF protection on all outbound server requests (such as webhook delivery), blocking requests to private IP ranges, localhost, and internal network addresses. All user inputs that could influence server-side requests are validated and sanitised.

Security You Can Trust

Australian data residency. End-to-end encryption. Complete audit trails. Start signing securely with 5 free envelopes.

Published 14 April 2026. Security practices and features are subject to continuous improvement.

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