CVE-2024-5739: line XSS (CVSS 6.1)

Description

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.

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CVSS v3.1 Score

6.1

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Weakness Type (CWE)

CWE-79 Cross-site Scripting (XSS)

Affected Products

Vendor	Product	Versions
linecorp	line	14.0.0 — 14.9.0

References

Other References

https://hackerone.com/reports/2284129 https://hackerone.com/reports/2284129

Frequently Asked Questions

What is CVE-2024-5739? +

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. It has a CVSS v3.1 base score of 6.1 (MEDIUM).

How severe is CVE-2024-5739? +

CVE-2024-5739 has a CVSS v3.1 score of 6.1 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2024-5739? +

CVE-2024-5739 affects products from linecorp, specifically: line. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-5739? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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