Seventy-six popular apps in the Apple App Store are vulnerable to silent interception of TLS-protected data due to a poor implementation of the cryptographic protocol.
According to researcher Will Strafach, who wrote on Medium, the apps are vulnerable to man-in-the-middle attacks. Data that is normally protected by Transport Layer Security can now be read or manipulated before it is forwarded to the company’s servers.
The apps mentioned by Medium can be fooled into providing readable data. The testing was done with an iPhone running iOS 10 and a proxy providing invalid TLS certificates.
The apps basically mishandle the way they transmit data that would normally be encrypted and will accept an encryption certificate regardless of who made it. This seems to be the result of not having a full understanding of the code input in the apps, which ends up breaking the validation set in place. Instead of using the certificate authorities they trust, the apps accept any certificate, which is a massive security problem.
The researcher used his own verify.ly web-based mobile app analysis service to research the problem. The 76 apps that were found to be lacking from a security point of view have a combined 18 million downloads, which should help you get an understanding about the severity of this problem.
For 33 of these apps, the vulnerability was deemed to be low risk, for 24 of them it was a medium risk, while the other 19 were considered to be high risk because of their confirmed ability to intercept financial or medical service login credentials and/or session authentication tokens for logged users.
These apps are vulnerable to attack, but the data that can be intercepted doesn’t pose a very high risk for users. They are: ooVoo, VivaVideo, Snap Upload for Snapchat, Uconnect Access, Volify, Uploader Free for Snapchat, Epic!, Mico, Safe Up for Snapchat, Tencent Cloud, Uploader for Snapchat, Safe Up for Snapchat, Tencent Cloud, Uploader for Snapchat, Huawei HiLink, VICE News, Trading 212 Forex & Stocks, CashApp, FreeMyApps, 1000 Friends for, YeeCall Messenger, InstaReports, Loops Live, Privat24, Private Browser, Cheetah Browser, AMAN BANK, FirstBank PR Mobile Banking, vpn free, GiftSage, Vpn One Click Professional, Music tube, AutoLotto: Powerball, MegaMillions Lottery Tickets, Foscam IP Camera Viewer by OWLR for Foscam IP Camera and Code Scanner by ScanLife: QR and Barcode Reader.
The medium and high-risk apps have not been named due to security risks. Instead, the researcher promises to post the list within 60 to 90 days after reaching out to the affected banks, medical providers and other developers of sensitive apps that are left vulnerable.
Until everything is fixed, people are advised not to use public WiFi networks, which is a security risk on its own. Companies offering these apps should work to fix them, while developers should be more careful when inserting network-related code and changing app behaviors.