iPhone Security Issue Opens Door to SMS Spoofing

ios messages iconJailbreak hacker and security researcher pod2g today revealed a newly-discovered security issue in all versions of iOS that could allow malicious parties to spoof SMS messages, making a recipient think that a message came from a trusted sender when it in fact came from the malicious party.

The issue is related to iOS's handling of User Data Header (UDH) information, an optional section of a text payload that allows users to specify certain information such as changing the reply-to number on a message to something other than the sending number. The iPhone's handling of this optional information could leave recipients open to targeted SMS spoofing attacks.

In the text payload, a section called UDH (User Data Header) is optional but defines lot of advanced features not all mobiles are compatible with. One of these options enables the user to change the reply address of the text. If the destination mobile is compatible with it, and if the receiver tries to answer to the text, he will not respond to the original number, but to the specified one.

Most carriers don't check this part of the message, which means one can write whatever he wants in this section : a special number like 911, or the number of somebody else.

In a good implementation of this feature, the receiver would see the original phone number and the reply-to one. On iPhone, when you see the message, it seems to come from the reply-to number, and you [lose] track of the origin.

pod2g highlights several ways in which malicious parties could take advantage of this flaw, including phishing attempts linking users to sites collecting personal information or spoofing messages for the purposes of creating false evidence or gaining a recipient's trust to enable further nefarious action.

In many cases the malicious party would need to know the name and number of a trusted contact of the recipient in order for their efforts to be effective, but the phishing example shows how malicious parties could cast broad nets hoping to snare users by pretending to be a common bank or other institution. But with the issue resulting in recipients being shown the reply-to address, an attack could be discovered or thwarted simply by replying to the message, as the return message would go to the familiar contact rather than the malicious one.

Related Forum: iPhone

Popular Stories

iPhone 17 Plus Feature

iPhone 17 Lineup Specs Detail Display Upgrade and New High-End Model

Monday July 22, 2024 4:33 am PDT by
Key details about the overall specifications of the iPhone 17 lineup have been shared by the leaker known as "Ice Universe," clarifying several important aspects of next year's devices. Reports in recent months have converged in agreement that Apple will discontinue the "Plus" iPhone model in 2025 while introducing an all-new iPhone 17 "Slim" model as an even more high-end option sitting...
iPhone SE 4 Vertical Camera Feature

iPhone SE 4 Rumored to Use Same Rear Chassis as iPhone 16

Friday July 19, 2024 7:16 am PDT by
Apple will adopt the same rear chassis manufacturing process for the iPhone SE 4 that it is using for the upcoming standard iPhone 16, claims a new rumor coming out of China. According to the Weibo-based leaker "Fixed Focus Digital," the backplate manufacturing process for the iPhone SE 4 is "exactly the same" as the standard model in Apple's upcoming iPhone 16 lineup, which is expected to...
Apple TV Plus Feature 2 Magenta and Blue

Apple TV+ Curbs Costs After Expensive Projects Fail to Capture Viewers

Monday July 22, 2024 5:11 am PDT by
Apple is scaling back its Hollywood spending after investing over $20 billion in original programming with limited success, Bloomberg reports. This shift comes after the streaming service, which launched in 2019, struggled to capture a significant share of the market, accounting for only 0.2% of TV viewership in the U.S., compared to Netflix's 8%. Despite heavy investment, critical acclaim,...
iPhone 16 Pro Sizes Feature

iPhone 16 Series Is Just Two Months Away: Everything We Know

Monday July 15, 2024 4:44 am PDT by
Apple typically releases its new iPhone series around mid-September, which means we are about two months out from the launch of the iPhone 16. Like the iPhone 15 series, this year's lineup is expected to stick with four models – iPhone 16, iPhone 16 Plus, iPhone 16 Pro, and iPhone 16 Pro Max – although there are plenty of design differences and new features to take into account. To bring ...
iPhone 17 Plus Feature Purple

These 5 Features Will Make the iPhone 17 the Biggest Update in Years

Monday July 22, 2024 4:02 pm PDT by
The upcoming iPhone 16 models that we're expecting to see in September are going to be quite similar to the iPhone 15 models, but rumors suggest that Apple is making big changes in 2025. We've been hearing hints of an all-new device in the iPhone lineup, and it may be the most expensive iPhone Apple has offered to date. New 'Slim' Design Rumors have taken to referring to the new iPhone 17...
iPhone SE 4 Thumb 1

iPhone SE 4 Rumored to Launch Early Next Year With OLED Display, 48MP Camera, and More

Monday July 22, 2024 7:22 am PDT by
The fourth-generation iPhone SE will offer a series of major upgrades over the current model, the leaker known as "Ice Universe" claims. The information was listed in a post on Weibo, which also detailed the specifications of the iPhone 17 lineup. As previously rumored, the fourth-generation iPhone SE is expected to feature Face ID and USB-C, marking a major upgrade from current and previous ...
bsod

Microsoft Blames European Commission for Major Worldwide Outage

Monday July 22, 2024 11:55 am PDT by
Last Friday, a major CrowdStrike outage impacted PCs running Microsoft Windows, causing worldwide issues affecting airlines, retailers, banks, hospitals, rail networks, and more. Computers were stuck in continuous recovery loops, rendering them unusable. The failure was caused by an update to the CrowdStrike Falcon antivirus software that auto-installed on Windows 10 PCs, but Mac and Linux...

Top Rated Comments

JAT Avatar
156 months ago
I think we could use a slight rewrite of the article. It didn't say "malicious party" nearly often enough for me.
Score: 9 Votes (Like | Disagree)
gotluck Avatar
156 months ago


Nope. :apple:

But i'm not surprised it didn't come from someone legit.

Pod2g is quite legit in my book.
Score: 6 Votes (Like | Disagree)
miniConvert Avatar
156 months ago
This makes no sense. You don't need to use UDH tricks to 'spoof' the sender ID on a text message, you just set whatever sender ID you want to use. Any text message can contain up to 16 digits or 11 alphanumeric characters of sender ID, and there's absolutely nothing that ensures this data is somehow verified or official.

Just as with an email you can, technically, originate it from wherever the hell you like, so can you with a text message.

This 'discovery' is not a discovery at all. In fact, it doesn't seem to be a problem at all. It would only be a problem if the sender ID displayed on the iPhone could be one thing, but the destination of the reply text messages could actually be something else that the user had no knowledge of. Correct me if I'm wrong, but in this instance the user is fully aware of the number they're texting. So no problem.

And yes, I know SMS.
Score: 6 Votes (Like | Disagree)
Uncle Ruckus Avatar
156 months ago
Apple get you act together.

Uncle Ruckus no relations.
Score: 6 Votes (Like | Disagree)
miniConvert Avatar
156 months ago
Agree with this. You are correct, this is not possible. When a reply-to address is specified iOS displays that and ignores the sender.
Yeah, I'm pretty sure this story is without merit and should be taken down. Simply a misunderstanding/lack of understanding about how SMS works.
Score: 5 Votes (Like | Disagree)
theBB Avatar
156 months ago
It is easy to spoof caller ID and fool every phone on earth. How is this any more dangerous?
Score: 5 Votes (Like | Disagree)