When it comes to securing your passwords and sensitive data, not all two-factor authentication (2FA) methods are created equal. Many services still offer SMS-based 2FA, but security-conscious platforms like Psono avoid it entirely in favor of stronger options like WebAuthn, YubiKey, and TOTP (Time-Based One-Time Passwords).
This isn't just a preference—it's a necessity for robust security. SMS-based 2FA has significant vulnerabilities, and real-world attacks have proven that it's an easy target for hackers. In this blog post, we’ll break down why SMS 2FA is weak and highlight real-world attacks that demonstrate its flaws.
🔒 The Weakness of SMS-Based 2FA
SMS-based authentication is vulnerable to multiple attack methods, including:
- SIM Swapping – Attackers trick mobile carriers into transferring a victim’s phone number to a new SIM, intercepting all SMS codes.
- SS7 Attacks – Exploiting flaws in the global Signaling System No. 7 (SS7) protocol to intercept SMS messages remotely.
- Phishing & Social Engineering – Tricking users into revealing SMS-based codes via fake login pages.
These risks make SMS-based 2FA one of the weakest forms of authentication.
🛡️ Why Psono Uses Stronger 2FA
Psono prioritizes security and only supports robust 2FA methods, including:
- WebAuthn (FIDO2) – Uses public-key cryptography and biometrics or hardware security keys (e.g., YubiKey).
- YubiKey & Other Security Keys – Physical tokens that require direct access to authenticate.
- TOTP (Google Authenticator, Authy, etc.) – One-time passwords generated on a device rather than transmitted over SMS.
These methods are significantly more secure because they are phishing-resistant, don’t rely on mobile carriers, and eliminate remote takeover risks.
📢 Real-World Attacks on SMS 2FA
To illustrate why Psono refuses to implement SMS-based authentication, here are real-world attacks that exploited its weaknesses:
1. China’s Targeting of U.S. Telecommunications (SS7 Exploits & More)
In February 2024, the FBI and CISA issued a joint warning about Chinese state-sponsored hackers targeting commercial telecommunications networks. These attacks exploited vulnerabilities in SS7—the protocol used for routing SMS messages. The attackers were able to intercept authentication messages, demonstrating how SMS 2FA can be compromised at a systemic level.
2. Twitter (X) CEO Jack Dorsey’s SIM Swap Attack (2019)
In 2019, Twitter’s CEO at the time, Jack Dorsey, had his account hijacked through a SIM swap attack. Hackers convinced his mobile carrier to transfer his phone number to their SIM card, allowing them to intercept 2FA SMS codes and gain control of his Twitter account.
3. Coinbase SIM Swap Attacks (2021) – Thousands of Dollars Stolen
In 2021, Coinbase disclosed that over 6,000 customers lost funds due to a massive SIM swap attack. Hackers reset victims’ passwords using intercepted SMS codes, gaining full control over accounts and stealing cryptocurrencies.
4. Reddit’s 2018 Data Breach – SMS 2FA Failed
In 2018, Reddit suffered a data breach where hackers accessed employee accounts despite SMS-based 2FA being enabled. Attackers used intercepted SMS codes to bypass authentication, exposing sensitive user data.
🚀 The Future of 2FA: Go Beyond SMS
If you’re still using SMS-based 2FA, it's time to switch to a stronger alternative like WebAuthn, YubiKey, or TOTP-based authentication. Psono’s commitment to security means it won’t compromise by offering SMS-based authentication.
Want to stay secure? Use hardware security keys, TOTP apps, or biometric authentication—never rely on SMS-based authentication alone.
Secure your accounts the right way—ditch SMS 2FA!
Frequently Asked Questions About Second-Factor Authentication (2FA)
What is Two-Factor Authentication (2FA) and why is it important?
Two-Factor Authentication (2FA) is an extra layer of security that requires two forms of authentication before granting access to an account. Instead of just using a password, you also need a second factor, such as:
- A one-time code from an authenticator app (TOTP)
- A hardware security key (e.g., YubiKey, Titan Security Key)
- Biometric authentication (fingerprint, face recognition)
It significantly reduces the risk of unauthorized access, even if an attacker gets your password.
What are the strongest types of 2FA?
The most secure second factors are those that are phishing-resistant and cannot be easily intercepted. These include:
- ✅ FIDO2/WebAuthn security keys (e.g., YubiKey, Titan Security Key)
- ✅ TOTP-based authentication apps (Google Authenticator, Authy, Aegis)
- ✅ Passkeys (passwordless authentication using biometrics or hardware security keys)
Weaker methods (to avoid):
- ❌ SMS-based 2FA – Susceptible to SIM swap attacks and SS7 exploits
- ❌ Email-based 2FA – Can be compromised if your email is hacked
Why is SMS-based 2FA considered insecure?
SMS-based 2FA is vulnerable to multiple attack methods, such as:
- SIM Swap Attacks – Hackers trick your mobile carrier into transferring your number to their SIM, letting them receive your 2FA codes.
- SS7 Exploits – Attackers intercept SMS messages by exploiting vulnerabilities in the telecom infrastructure.
- Phishing Attacks – Fake websites trick users into entering their SMS codes, allowing attackers to log in.
🔹 Better alternatives: Use hardware security keys or TOTP apps instead of SMS 2FA.
What happens if I lose my second factor (e.g., phone, YubiKey)?
If you lose access to your second factor, you can recover your account by:
- Using backup codes – Many services provide one-time backup codes when setting up 2FA. Store them securely.
- Using a backup device – Some authenticator apps allow multiple devices to store TOTP codes.
- Contacting support – Some services offer account recovery, but this can be slow and requires proof of identity.
- Using a second hardware key – If your service supports it, register multiple security keys (primary + backup).
🔹 Pro tip: Always set up multiple authentication methods in case one fails.
Can hackers bypass 2FA?
While 2FA significantly improves security, some methods can be bypassed with advanced attacks:
🚨 Common attack methods:
- Phishing attacks – Fake login pages trick users into entering both their password and 2FA code.
- Man-in-the-Middle (MitM) attacks – Intercepting authentication tokens over insecure networks.
- SIM swapping – Redirecting SMS codes to an attacker’s phone.
✅ How to prevent it:
- Use phishing-resistant authentication (WebAuthn, passkeys, security keys).
- Enable device-bound authentication (so tokens cannot be reused remotely).
- Be cautious of suspicious login pages – Always verify URLs before entering credentials.
