Why you should avoid using one-time passwords sent via text messages

Image Credits: UnsplashImage Credits: Unsplash
  • One-time passwords sent via text are susceptible to SIM swap attacks, phishing, and SMS interception.
  • App-based MFA, passwordless authentication, and hardware tokens offer more robust security.
  • Adopting these alternatives can significantly reduce the risk of unauthorized access to your accounts.

In our digital age, securing online accounts has never been more critical. One-time passwords (OTPs) sent by text message have become a common method for adding an extra layer of security. However, recent developments have shown that this method is fraught with vulnerabilities that can be exploited by cybercriminals. Here’s why you should avoid using OTPs sent by text and consider more secure alternatives.

The Vulnerabilities of SMS OTPs

One-time passwords are designed to be used once and provide a temporary code for logging into websites, authorizing financial transactions, or accessing confidential data. While this may seem secure, the reality is quite different. According to cybersecurity experts, OTPs sent via SMS are susceptible to several types of attacks:

SIM Swap Attacks: In a SIM swap attack, a hacker tricks the mobile carrier into transferring the victim's phone number to a new SIM card. Once the hacker has control of the phone number, they can intercept the OTP sent via text message and gain unauthorized access to the victim's accounts.

Phishing Attacks: Phishing remains one of the most effective methods for cybercriminals. By creating fake login pages, attackers can trick users into entering their OTPs, which are then used to access the victim's accounts.

SMS Interception: The SMS protocol itself is not very secure. Hackers can intercept text messages containing OTPs, especially if the user is connected to an unsecured Wi-Fi network.

Cheryl Winokur Munk highlights, "One-time passwords have become a common method to restore consumer access to apps, but they are vulnerable to hacks". This vulnerability makes SMS OTPs an unreliable method for securing sensitive information.

Real-World Examples of OTP Vulnerabilities

The breach of Twilio, a company that promotes two-factor authentication, is a notable example. Phishers targeted Cloudflare using OTPs issued by Okta, a security company. This incident underscores the need to evaluate the effectiveness of OTPs and consider alternative security measures.

Better Alternatives to SMS OTPs

Given the vulnerabilities of SMS OTPs, it’s crucial to explore more secure authentication methods:

App-Based Multi-Factor Authentication (MFA): Apps like Google Authenticator and Microsoft Authenticator generate OTPs within the app itself, making them less susceptible to interception. These apps use time-based algorithms to generate codes that are valid for a short period, adding an extra layer of security.

Passwordless Authentication: This method removes the password entirely from the authentication process. Instead, it uses cryptographic keys tied to the user’s device and biometrics. This approach significantly reduces the risk of password-based attacks and is considered one of the most secure authentication methods available.

Hardware Tokens: Devices like YubiKey provide a physical form of authentication. These tokens generate OTPs or use cryptographic keys to authenticate the user, making it extremely difficult for attackers to gain access without the physical device.

While one-time passwords sent via text message offer a convenient form of two-factor authentication, they are not without significant risks. From SIM swap attacks to phishing and SMS interception, the vulnerabilities are too substantial to ignore. For a more secure digital experience, consider adopting app-based MFA, passwordless authentication, or hardware tokens. By doing so, you can significantly enhance your account security and protect your sensitive information from cyber threats.


Technology Singapore
Image Credits: Unsplash
TechnologyJuly 8, 2025 at 11:30:00 AM

Singapore’s fastest EV charger set to join national network by Q4 2025

When headlines tout a new electric vehicle (EV) charger capable of adding 200 kilometers of range in five minutes, it’s easy to focus...

Technology
Image Credits: Unsplash
TechnologyJuly 8, 2025 at 12:00:00 AM

Why doomscrolling happens—and how to break free gently

You’ve already brushed your teeth. The lights are off. The sheets are cool. But your thumb is still scrolling. Headline after headline. Fire....

Technology
Image Credits: Unsplash
TechnologyJuly 7, 2025 at 4:30:00 PM

What started as a joke became something darker

It’s easy to laugh. That’s the danger. A meme flashes by on your feed. It's absurd, slightly offensive, maybe oddly funny. You scroll,...

Technology
Image Credits: Unsplash
TechnologyJuly 7, 2025 at 2:30:00 PM

What keeps Google on top in the search engine game

You open your laptop. The screen flickers to life. You tap a few keys, barely think about where the query goes, and within...

Technology Singapore
Image Credits: Unsplash
TechnologyJuly 7, 2025 at 2:00:00 PM

AI cheating still rare in Singapore universities, but risks are growing

Somewhere on Reddit, a university student vents that they got zero marks because ChatGPT helped with an assignment. The comments flood in. Some...

Technology
Image Credits: Unsplash
TechnologyJune 27, 2025 at 8:00:00 PM

Why the world’s most helpful AI tool is also its most quietly destabilizing force

ChatGPT, OpenAI’s generative text model, has become a fixture in how we write, plan, and problem-solve. From coding scripts to marketing copy, homework...

Technology
Image Credits: Unsplash
TechnologyJune 22, 2025 at 1:00:00 PM

Why disappearing from social media feels like reclaiming myself

I didn’t make an announcement. I didn’t write a goodbye post or warn followers I’d be “taking a break.” One day I simply...

Culture
Image Credits: Unsplash
CultureJune 21, 2025 at 11:00:00 AM

How assistive tech is redefining work

We used to treat accessibility like a checkbox. Install the ramp, add closed captions, enlarge the font. Done. At least that’s how most...

Culture
Image Credits: Unsplash
CultureJune 20, 2025 at 3:00:00 PM

Handwriting isn’t dead. It’s a strategic pause.

Digital tools accelerate input, not insight. You can generate 500 words in a second. You can transcribe a Zoom call before you even...

Technology
Image Credits: Unsplash
TechnologyJune 19, 2025 at 4:00:00 PM

TikTok, Instagram, YouTube—can overuse actually affect your brain?

Doomscrolling. Instagram obsessions. Mindless YouTube rabbit holes that start with “just one more” and end two hours later in a haze of mukbangs,...

Financial Planning
Image Credits: Unsplash
Financial PlanningJune 18, 2025 at 7:30:00 PM

How one search can save your savings

Every year, countless investors—many of them new to the world of personal finance—lose their hard-earned savings to scams that could have been easily...

Financial Planning
Image Credits: Unsplash
Financial PlanningJune 11, 2025 at 7:00:00 PM

What to do after a cyberattack

So, another company got hacked. Your inbox lights up with a “We care about your privacy” email, and suddenly you’re wondering if some...

Load More