By Talal Haj Bakry and Tommy Mysk

UPDATE (AUGUST 16, 2020): More apps crossed out *

UPDATE (JUNE 30, 2020): The list of apps in the original report from March 2020 is NOT an exhaustive list. We examined a sample of popular apps, and listed the ones that exhibited the behavior of excessive clipboard access. Many apps have been updated since then. In light of that, we tested the apps again. The apps that stopped reading the clipboard are crossed out.

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Videos

Two apps; one snoops on the clipboard, the other doesn’t

Exploit of the Universal Clipboard on Mac

Method to view pasteboard events using Xcode

Summary

This article provides an investigation of some popular apps that frequently access the pasteboard without user consent. These apps range from popular games and social networking apps, to news apps of major news organizations. We found that many apps quietly read any text found in the pasteboard every time the app is opened. Text left in the pasteboard could be as simple as a shopping list, or could be something more sensitive: passwords, account numbers, etc.

Introduction

Apps on iOS and iPadOS have unrestricted access to the system-wide general pasteboard, also referred to as the clipboard. The potential security risks of this vulnerability have been thoroughly discussed in a previous article: Precise Location Information Leaking Through System Pasteboard. We have explored popular and top apps available on the App Store and observed their behaviour using the standard Apple development tools. The results show that many apps frequently access the pasteboard and read its content without user consent, albeit only text-based data.

The apps we chose in this investigation belong to various App Store categories, e.g. games, social networking, and news. As we described in our pervious article, the severity of the pasteboard vulnerability is greatest when popular and frequently-used apps exploit it. Thus, we targeted a variety of popular apps we found on the top lists of the App Store.

Methodology

Apple provides Xcode and Xcode Command Line tools for developers to build apps for iOS, iPadOS, and macOS. We used these official tools to monitor and analyze the behavior of apps installed on our iOS and iPadOS devices. The method is simple: Once we connect and pair the devices with Xcode, we can read the system log of the device. Fortunately, all pasteboard events are clearly logged. Figure 1 shows an example of the system log output when the Fox News app is opened. The following explains the key information in the log output:

The logs output all events, and is filtered by the keyword “pasteboard”

The highlighted event in Figure 1 shows when the Fox News app requested access to the pasteboard with ID com.apple.UIKit.pboard.general . This is the ID of the system-wide pasteboard

. This is the ID of the system-wide pasteboard BundleID com.foxnews.foxnews is the ID that uniquely identifies the Fox News app on the App Store

is the ID that uniquely identifies the Fox News app on the App Store The event message that starts with “Loading item …” in Figure 2, indicates that the app has read the content of the pasteboard.

The type public.utf8-plain-text indicates that the content that the app has read is text.

This method can be performed by any iOS or Mac developer.

Criteria

We include any app that requests and reads the content of the system-wide pasteboard every time it’s opened, and consider it to be highly suspicious. There are games and apps that do not provide any UI that deals with text, yet they read the text content of the pasteboard every time they’re opened.

Every app that is popular or on a top list according to the App Store rankings qualifies to be part of this investigation. However, we picked a diverse collection of apps to provide proof that such a suspicious practice of snooping on the pasteboard exists in many apps.

There is a considerable number of apps that only read the content of the pasteboard on launch. That is, the app reads the pasteboard only when it is opened for the first time. The next time it reads the pasteboard again is when the app is quit and relaunched. Although such a behavior is also suspicious, we decided to exclude such apps and focus on the ones that access the pasteboard more frequently.

As noted in our previous article, an app that accesses the pasteboard can also read what has been copied on a Mac if Universal Clipboard is enabled.

Findings

While unrestricted access to the pasteboard allow apps to read any data type, all the apps we investigated for this article have only requested access to text data. In other words, they are only interested in reading text and ignore other data types that may have been copied to the pasteboard, such as photos and PDF documents. Surprisingly, none of the widgets that were tested accessed the pasteboard.

Our findings only documented apps that read the pasteboard every time the app is opened. However, apps can delay snooping on the pasteboard until some time or event takes places (e.g. signing up), hence are not included in our findings.

List of Apps

This section summarizes the list of apps that snoop on the pasteboard every time the app is opened. The apps are listed alphabetically in the following format:

App Name — BundleID

UPDATE (AUGUST 16, 2020): More apps crossed out *

UPDATE (JUNE 30, 2020): The list of apps in the original report from March 2020 is NOT an exhaustive list. We examined a sample of popular apps, and listed the ones that exhibited the behavior of excessive clipboard access. Many apps have been updated since then. In light of that, we tested the apps again. The apps that stopped reading the clipboard are crossed out.

We thank developers who updated their apps to fix this privacy issue.

News

ABC News — com.abcnews.ABCNews

Al Jazeera English — ajenglishiphone

CBC News — ca.cbc.CBCNews

CBS News — com.H443NM7F8H.CBSNews

CNBC — com.nbcuni.cnbc.cnbcrtipad *

* Fox News — com.foxnews.foxnews *

* News Break — com.particlenews.newsbreak *

* New York Times — com.nytimes.NYTimes *

* NPR — org.npr.nprnews

org.npr.nprnews ntv Nachrichten — de.n-tv.n-tvmobil

Reuters — com.thomsonreuters.Reuters

com.thomsonreuters.Reuters Russia Today — com.rt.RTNewsEnglish *

* Stern Nachrichten — de.grunerundjahr.sternneu

de.grunerundjahr.sternneu The Economist — com.economist.lamarr *

* The Huffington Post — com.huffingtonpost.HuffingtonPost *

* The Wall Street Journal — com.dowjones.WSJ.ipad *

* Vice News — com.vice.news.VICE-News *

Games

8 Ball Pool™ — com.miniclip.8ballpoolmult

AMAZE!!! — com.amaze.game

Bejeweled — com.ea.ios.bejeweledskies

com.ea.ios.bejeweledskies Block Puzzle — Game.BlockPuzzle

Game.BlockPuzzle Classic Bejeweled — com.popcap.ios.Bej3

Classic Bejeweled HD — com.popcap.ios.Bej3HD

FlipTheGun — com.playgendary.flipgun

com.playgendary.flipgun Fruit Ninja — com.halfbrick.FruitNinjaLite *

* Golfmasters — com.playgendary.sportmasterstwo

com.playgendary.sportmasterstwo Letter Soup — com.candywriter.apollo7

Love Nikki — com.elex.nikki

com.elex.nikki My Emma — com.crazylabs.myemma

com.crazylabs.myemma Plants vs. Zombies™ Heroes — com.ea.ios.pvzheroes

com.ea.ios.pvzheroes Pooking – Billiards City — com.pool.club.billiards.city

com.pool.club.billiards.city PUBG Mobile — com.tencent.ig

Tomb of the Mask — com.happymagenta.fromcore

Tomb of the Mask: Color — com.happymagenta.totm2

Total Party Kill — com.adventureislands.totalpartykill

com.adventureislands.totalpartykill Watermarbling — com.hydro.dipping

Social Networking

TikTok — com.zhiliaoapp.musically

ToTalk — totalk.gofeiyu.com

totalk.gofeiyu.com Tok — com.SimpleDate.Tok

com.SimpleDate.Tok Truecaller — com.truesoftware.TrueCallerOther

Viber — com.viber

Weibo — com.sina.weibo *

* Zoosk — com.zoosk.Zoosk

Other

10% Happier: Meditation — com.changecollective.tenpercenthappier

5-0 Radio Police Scanner — com.smartestapple.50radiofree

Accuweather — com.yourcompany.TestWithCustomTabs *

* AliExpress Shopping App — com.alibaba.iAliexpress *

* Bed Bath & Beyond — com.digby.bedbathbeyond *

* Dazn — com.dazn.theApp

Hotels.com — com.hotels.HotelsNearMe

Hotel Tonight — com.hoteltonight.prod

Overstock — com.overstock.app

com.overstock.app Pigment – Adult Coloring Book — com.pixite.pigment *

* Recolor Coloring Book to Color — com.sumoing.ReColor

Sky Ticket — de.sky.skyonline *

* The Weather Network — com.theweathernetwork.weathereyeiphone *

Conclusion

Access to the pasteboard in iOS and iPadOS requires no app permission as of iOS 13.3. While the pasteboard provides the ease of sharing data between various apps, it poses a risk of exposing private and personal data to suspicious apps. We have investigated many popular apps in the App Store and found that they frequently access the pasteboard without the user being aware. Our investigation confirms that many popular apps read the text content of the pasteboard. However, it is not clear what the apps do with the data. To prevent apps from exploiting the pasteboard, Apple must act.

Media Coverage

This article was well-received in social media and has been covered by several tech websites. The following list provides links to the coverage: