Why Email Attachments Are Risky and What to Use Instead

Tax returns, contracts, medical records, ID copies — people attach sensitive documents to emails every single day. It feels so natural that most never stop to consider the risk.

But email attachments are far more dangerous than you think.

5 Reasons Email Attachments Are Dangerous

1. Encryption in Transit Is Not Guaranteed

Most email services use TLS encryption, but this isn't guaranteed across every hop. Between your mail server and the recipient's, the connection might pass through servers that don't enforce encryption. Corporate mail servers and smaller email providers are especially vulnerable.

2. Files Are Stored Permanently on Servers

A sent email creates copies in at least three places:

• The sender's Sent folder
• The recipient's inbox
• Server-side backups

Even after deletion, server backups can retain the files for months or years.

3. Emails Can Be Forwarded Endlessly

An email with attachments can be forwarded to anyone with a single click. The original sender has no way of knowing how many people have received copies of their sensitive files.

4. Email Servers Are Prime Breach Targets

Email servers are high-value targets for attackers. A single security breach can expose thousands of emails and attachments at once.

5. Size Limits Push People to Insecure Workarounds

Most email providers cap attachments at 25MB. This drives people to use insecure free file-sharing services or to send files without encryption — trading security for convenience.

Dangerous Attachments People Send via Email

Document Type	Risk Level	Damage If Leaked
Tax returns	Very High	Identity theft, financial fraud
Contracts	High	Business secrets exposed, legal disputes
Medical records	Very High	Privacy violation, insurance fraud
ID copies	Very High	Identity theft, unauthorized loans
Password lists	Critical	Account takeover, cascading breaches
Pay stubs	High	Personal financial data exposed
Legal documents	High	Litigation-sensitive information leaked

Safer Alternatives

Alternative 1: Password-Protected Links (Recommended)

Instead of attaching sensitive files directly, share them through password-protected links.

Benefits:

• Only people with the password can access the content
• Expiration dates prevent permanent exposure
• Files are not stored on email servers
• Access logs let you track who viewed the content

Alternative 2: Secret Memos

For text-based sensitive information like passwords, API keys, or account numbers, use a secret memo instead of creating a file attachment. Set an expiration period and the content becomes inaccessible automatically.

Alternative 3: Encrypted File-Sharing Services

For large files, use dedicated file-sharing services with end-to-end encryption. Be cautious with free services and verify their security claims before use.

Email Attachment vs Secure Link Sharing

Factor	Email Attachment	Password-Protected Link
Transit encryption	Partial	Full HTTPS encryption
Server storage	Permanent (including backups)	Inaccessible after expiration
Forwarding control	Impossible	Password acts as barrier
Access tracking	Impossible	Available
Expiration	Not available	Configurable
File size limit	25MB	None (URL-based)
Damage scope if leaked	Unlimited	Limited by expiration and password

How to Share Securely with LOCK.PUB

When you need to send sensitive information via email, use this approach instead.

For Text-Based Information

Passwords, account numbers, authentication codes, and similar text data belong in a LOCK.PUB secret memo.

1. Create a secret memo on LOCK.PUB
2. Enter the sensitive text information
3. Set a password and expiration period
4. Send the generated link via email
5. Share the password via phone call or text message

For Files and URLs

If your document is stored in the cloud, wrap the URL in a password-protected link.

1. Upload the file to cloud storage
2. Create a LOCK.PUB password-protected link for the share URL
3. Set the shortest practical expiration period
4. Send the link via email
5. Share the password through a separate channel

Real-World Scenarios

Scenario 1: Sending Tax Documents to an Accountant

Old way: Attach tax return PDFs to an email.

Secure way: Upload tax documents to cloud storage, share via LOCK.PUB password-protected link. Email the link to your accountant, call them with the password. Set the link to expire after filing is complete.

Scenario 2: Sharing Login Credentials with a New Employee

Old way: Type usernames and passwords in the email body.

Secure way: Create a LOCK.PUB secret memo with the credentials. Set 24-hour expiration. Send the link via company chat, share the password in person.

Scenario 3: Sending Legal Documents to an Attorney

Old way: Attach scanned contracts to an email.

Secure way: Upload scans to cloud storage, share via LOCK.PUB link. Set automatic expiration for when the case concludes.

Email Security Checklist

Before hitting send, ask yourself:

• What happens if this information gets leaked?
• Can I share a link instead of attaching the file?
• Can I set an expiration date?
• Can I send the password through a different channel?
• Can I ask the recipient to confirm receipt and delete?

If any of these apply, use a password-protected link instead of an email attachment.

Summary

Email attachments are convenient but unsuitable for sensitive information. They get stored permanently on servers, forwarded without limit, and are impossible to control after sending. Password-protected links with expiration dates dramatically reduce these risks.

Create your secure link now.

Create a Password-Protected Link