Smishing Attacks: How SMS Phishing Works and How to Stop It

Your phone buzzes. A text from your “bank” says suspicious activity was detected on your account. Click here to verify. The link looks legitimate. The message is urgent.

You’re already reaching for the link before you’ve finished reading.

That reaction is exactly why smishing works. SMS phishing succeeds where email fails because we’ve spent years training ourselves to distrust our inboxes. Nobody taught us to be suspicious of texts.

I’ve watched security-conscious people who would never click an email link tap a suspicious SMS without hesitation. The psychology is different:

Texts feel personal. Email comes from companies. Texts come from people you know. When a text arrives, your brain defaults to trust.

There’s no time to think. Email sits in your inbox until you’re ready. A text notification demands immediate attention. You’re responding on instinct, not analysis.

You can’t see where links go. On a phone screen, URLs get truncated. That suspicious domain? Hidden behind ”…” in a tiny font. This is the same URL deception that works in email, but worse on mobile.

Your phone has no defenses. Your email has spam filters, phishing detection, attachment scanning. Your SMS app? Nothing.

“Chase Alert: Unusual activity detected on your account. Verify immediately: chase-verify-security.com”

These messages exploit:

• Trust in bank security alerts
• Fear of financial loss
• Urgency of fraud prevention

“USPS: Your package cannot be delivered. Update delivery preferences: usps-redelivery.net”

Effective because:

• Everyone receives packages
• Delivery issues feel plausible
• Small “redelivery fees” seem reasonable

“Google: Someone is trying to sign into your account. Reply YES if this was you, or click here to secure your account.”

This attack intercepts legitimate login attempts by tricking users into revealing authentication codes.

“Apple Support: Your iCloud is full and backups are failing. Upgrade now to prevent data loss: icloud-upgrade-storage.com”

Targets users’ fear of losing photos and data.

“IRS: You have an outstanding tax obligation. Avoid legal action by paying immediately: irs-payment-portal.com”

Uses authority and fear of government penalties.

Unexpected contact. Legitimate organizations rarely initiate sensitive communications via SMS.

Urgency language. “Immediately,” “urgent,” “within 24 hours” pressure quick action over careful evaluation.

Generic greetings. Your bank knows your name. “Dear Customer” suggests fraud.

Shortened or suspicious URLs. Bit.ly links or domains that don’t match the claimed sender.

Requests for sensitive info. Legitimate organizations don’t ask for passwords, PINs, or full account numbers via text.

Poor grammar or formatting. Professional organizations have professional communications.

Attackers rarely use just one channel. A smishing text might tell you to call a number (leading to vishing). A vishing call might reference a “confirmation text” they’re about to send. The channels reinforce each other. This kind of multi-channel approach is a hallmark of social engineering attacks.

The difference between them comes down to what makes each channel vulnerable:

• Email phishing gives attackers more space to craft convincing messages, but we’ve learned to be suspicious
• Smishing exploits the trust and urgency built into text messaging
• Vishing adds real-time social pressure that’s almost impossible to resist

Some attackers combine smishing with barrel phishing techniques, sending an innocuous first text to build rapport before following up with the malicious link.

If you get suspicious communication on one channel, expect attempts on others.

Never click links in unexpected texts. Navigate directly to services by typing URLs or using apps.

Verify independently. If a text claims to be from your bank, call the number on your card, not any number in the message.

Enable spam filtering. Both iOS and Android offer SMS spam detection. Enable it.

Report smishing. Forward suspicious texts to 7726 (SPAM) to report to carriers.

Don’t respond. Responding (even to say “stop”) confirms your number is active.

Implement mobile device management (MDM) with security policies on company devices, including SMS threat detection. A strong mobile security training program is the foundation.

Include smishing scenarios in security awareness training. Mobile threats are undertrained relative to email.

Establish clear policies that your organization will never request credentials or sensitive data via SMS.

Make it easy for employees to report suspicious texts to security teams.

Include SMS-based simulations in phishing simulation programs where possible. Interactive smishing training exercises give employees practice identifying text-based attacks before real ones arrive.

1. Delete the message
2. Block the sender
3. Report to 7726 (SPAM)

1. Close the page immediately
2. Clear browser data
3. Monitor for unusual activity

1. Change password immediately on the real site
2. Enable 2FA if not already active
3. Contact the real organization’s fraud department
4. Monitor accounts for unauthorized activity
5. Consider identity theft protection if personal information was shared

Smishing attacks increased 700% during 2021-2022 according to SlashNext’s annual threat report, as attackers recognized the opportunity. Contributing factors:

• People increasingly handle sensitive transactions on phones
• Security training focuses on email while mobile threats are undertrained
• SMS lacks the authentication and filtering infrastructure email has developed
• Increased reliance on delivery services and mobile banking created new attack surfaces

A 2023 smishing campaign impersonated USPS, UPS, and FedEx simultaneously:

Attack pattern:

1. Text claiming delivery issue
2. Link to credential harvesting page mimicking carrier site
3. Request for “small redelivery fee” ($1.99)
4. Payment form capturing full credit card details

Scale: Millions of texts sent during holiday shipping season.

Effectiveness: Higher success rate than equivalent email phishing due to timing (everyone expected packages) and mobile trust dynamics.

Lesson: Seasonal context dramatically increases smishing effectiveness. Training should address current attack patterns.

We’ve spent two decades building email security. Spam filters, phishing detection, user training. And it worked. Click rates on phishing emails have dropped.

So attackers moved to SMS, where none of those defenses exist.

The same skepticism you’ve learned to apply to email needs to extend to every channel. That “bank alert” text? Call your bank using the number on your card. That “delivery notification”? Check the tracking on the carrier’s actual website.

It feels paranoid. It’s not. It’s just how we have to operate now.

Build the instincts that catch smishing before you click. Try our free Smishing exercise with a realistic SMS attack scenario, or explore our full security awareness training catalogue for more interactive exercises.