New U.S. Guidelines Could Halt Use of SMS for Two-Factor Authentication

The US National Institute for Standards and Technology has released a new draft of its Digital Authentication Guideline, which sets the rules that all authentication software eventually follows. In the document, NIST deprecates the implementation of SMS as a method with which users validate a second level of security on various accounts, "no longer" allowing its use in future guidelines as it is considered not secure enough (via TechCrunch).

iOS two-factor authentication

Two-factor authentication via SMS (left) and an alternative trusted iOS device (right)

Setting up two-factor authentication through text messages is one of the most popular ways users add another layer of security onto an account, on top of a basic password, including those for Apple's own software, like Apple ID and iCloud. Other than SMS, Apple allows users to implement two-factor authentication through a simple push notification sent to another "trusted device," or a phone call.

If the out of band verification is to be made using a SMS message on a public mobile telephone network, the verifier SHALL verify that the pre-registered telephone number being used is actually associated with a mobile network and not with a VoIP (or other software-based) service. It then sends the SMS message to the pre-registered telephone number. Changing the pre-registered telephone number SHALL NOT be possible without two-factor authentication at the time of the change. OOB using SMS is deprecated, and will no longer be allowed in future releases of this guidance.

The new guidelines also make a point for companies to ensure that two-factor authentication notifications aren't going through a VoIP service, which could be easily compromised. NIST also includes "limited use" of biometrics as a way for users to gain access to their second layer of authentication, meaning Apple could pivot to Touch ID as an alternative if SMS support for the security feature officially comes to an end.

Popular Stories

iPhone 17 Pro Iridescent Feature 2

iPhone 17 Pro Clear Case Leak Reveals Three Key Changes

Sunday August 31, 2025 1:26 pm PDT by
Apple is expected to unveil the iPhone 17 series on Tuesday, September 9, and last-minute rumors about the devices continue to surface. The latest info comes from a leaker known as Majin Bu, who has shared alleged images of Apple's Clear Case for the iPhone 17 Pro and Pro Max, or at least replicas. Image Credit: @MajinBuOfficial The images show three alleged changes compared to Apple's iP...
iPhone 17 Pro Dark Blue and Orange

iPhone 17 Release Date, Pre-Orders, and What to Expect

Thursday August 28, 2025 4:08 am PDT by
An iPhone 17 announcement is a dead cert for September 2025 – Apple has already sent out invites for an "Awe dropping" event on Tuesday, September 9 at the Apple Park campus in Cupertino, California. The timing follows Apple's trend of introducing new iPhone models annually in the fall. At the event, Apple is expected to unveil its new-generation iPhone 17, an all-new ultra-thin iPhone 17...
iphone 16 pro ghost hand

iPhone 17 Pro: 5 Reasons Not to Upgrade This Year

Monday September 1, 2025 4:35 am PDT by
Apple will launch its new iPhone 17 series this month, and the iPhone 17 Pro models are expected to get a new design for the rear casing and the camera area. But more significant changes to the lineup are not expected until next year, when the iPhone 18 models arrive. If you're thinking of trading in your iPhone for this year's latest, consider the following features rumored to be coming to...
iPhone 17 Pro Iridescent Feature 2

iPhone 17 and iPhone 17 Pro Prices Estimated Ahead of Apple Event Next Week

Tuesday September 2, 2025 1:50 pm PDT by
Just one week before Apple is expected to unveil the iPhone 17 series, an analyst has shared new price estimates for the devices. Here are J.P. Morgan analyst Samik Chatterjee's price estimates for the iPhone 17 series in the United States, according to 9to5Mac: Model Starting Price Model Starting Price Change iPhone 16 $799 iPhone 17 ...
xiaomi apple ad india

Apple and Samsung Push Back Against Xiaomi's Bold India Ads

Friday August 29, 2025 4:54 am PDT by
Apple and Samsung have reportedly issued cease-and-desist notices to Xiaomi in India for an ad campaign that directly compares the rivals' devices to Xiaomi's products. The two companies have threatened the Chinese vendor with legal action, calling the ads "disparaging." Ads have appeared in local print media and on social media that take pot shots at the competitors' premium offerings. One...
iOS 18 on iPhone Arrow Down

Apple Preparing iOS 18.7 for iPhones as iOS 26 Release Date Nears

Sunday August 31, 2025 4:35 pm PDT by
Apple is preparing to release iOS 18.7 for compatible iPhone models, according to evidence of the update in the MacRumors visitor logs. We expect iOS 18.7 to be released in September, alongside iOS 26. The update will likely include fixes for security vulnerabilities, but little else. iOS 18.7 will be one of the final updates ever released for the iPhone XS, iPhone XS Max, and iPhone XR,...
iPhone 17 Pro 3 4ths Perspective Aluminum Camera Module 1

New iPhone 17 Pro Details: Brighter Display, Best Battery Life, and More

Wednesday September 3, 2025 5:33 am PDT by
Apple's iPhone 17 Pro and iPhone 17 Pro Max models will feature a number of significant display, thermal, and battery improvements, according to new late-stage rumors. According to the Weibo leaker known as "Instant Digital," the iPhone 17 Pro models will feature displays with higher brightness, making it more suitable for use in direct sunlight for prolonged periods. The iPhone 16 Pro and...

Top Rated Comments

2457282 Avatar
119 months ago
I thought our government was trying to weaken security so they can access our phones. Who at NIST made this mistake of proposing a verification process that was more secure? Probably fired by the end of the week. :eek::D:p:cool:
Score: 20 Votes (Like | Disagree)
John Mcgregor Avatar
119 months ago
Apple can send an iMessage.
Score: 10 Votes (Like | Disagree)
gwhizkids Avatar
119 months ago
But its a much better way than doing nothing at all. Personally, we need to get to a whole new paradigm of authentication, period. Deprecate the password!
Score: 7 Votes (Like | Disagree)
Iconoclysm Avatar
119 months ago
I thought our government was trying to weaken security so they can access our phones. Who at NIST made this mistake of proposing a verification process that was more secure? Probably fired by the end of the week. :eek::D:p:cool:
If the government convinces you to use TouchID, they can force you to unlock your phone without a PIN.
Score: 6 Votes (Like | Disagree)
bdhokie Avatar
119 months ago
While it may not be perfect, the suggestion everyone should use an app eliminates any two factor authentication for small companies /developers who may not have those resources starting out. Instead of deprecating SMS, which is better than nothing, why not recommend it as a last resort?
Score: 5 Votes (Like | Disagree)
big-ted Avatar
119 months ago
Good.

SMS is a piss poor way of doing 2FA and lazy companies need to move towards apps such as google authenticator, authy, e.g.
You are assuming that everyone on the planet has a smart phone
Score: 5 Votes (Like | Disagree)