Lack of TLS certificate verification in log transmission of a financial module within LINE client for iOS prior to 13.16.0.

LINE client for iOS prior to 15.4 allows man-in-the-middle attacks due to improper SSL/TLS certificate validation in an integrated financial SDK. The SDK interfered with the application's network processing, causing server certificate verification to be disabled for a significant portion of network traffic, which could allow a network-adjacent attacker to intercept or modify encrypted communications.

LINE client for iOS before 11.15.0 might expose authentication information for a certain service to external entities under certain conditions. This is usually impossible, but in combination with a server-side bug, attackers could get this information.

LINE client for iOS versions prior to 26.3.0 contains a vulnerability in the in-app browser where opening a crafted web page can repeatedly trigger OS-level dialogs due to insufficient safeguards when handling arbitrary URL schemes, potentially causing the iOS device to become temporarily inoperable.

The in-app browser of LINE client for iOS versions below 14.9.0 contains a Universal XSS (UXSS) vulnerability. This vulnerability allows for cross-site scripting (XSS) where arbitrary JavaScript can be executed in the top frame from an embedded iframe on any displayed web site within the in-app browser. The in-app browser is usually opened by tapping on URLs contained in chat messages, and for the attack to be successful, the victim must trigger a click event on a malicious iframe. If an iframe embedded in any website can be controlled by an attacker, this vulnerability could be exploited to capture or alter content displayed in the top frame, as well as user session information. This vulnerability affects LINE client for iOS versions below 14.9.0 and does not affect other LINE clients such as LINE client for Android. Please update LINE client for iOS to version 14.9.0 or higher.

LINE client for iOS before 10.16.3 allows cross site script with specific header in WebView.

LINE client for iOS prior to 15.19 allows UI spoofing due to inconsistencies between the navigation state and the in-app browser's user interface, which could create confusion about the trust context of displayed pages or interactive elements under specific conditions.

The in-app browser in LINE client for iOS versions prior to 14.14 is vulnerable to address bar spoofing, which could allow attackers to execute malicious JavaScript within iframes while displaying trusted URLs, enabling phishing attacks through overlaid malicious content.