CVE-2025-30466 is a critical security vulnerability affecting Apple’s iOS and iPadOS platforms, specifically related to the Safari web browser and underlying web rendering engines. The vulnerability allows a malicious website to bypass the Same Origin Policy (SOP), a fundamental security mechanism that restricts how documents or scripts loaded from one origin can interact with resources from another origin. SOP is essential for preventing cross-site scripting (XSS) and data theft between websites. The bypass occurs due to improper state management within the browser, enabling an attacker-controlled website to access or manipulate data from other origins without proper authorization. This can lead to unauthorized access to sensitive information, session hijacking, or execution of malicious scripts with elevated privileges. The issue has been addressed in Safari 18.4, iOS 18.4, iPadOS 18.4, visionOS 2.4, and macOS Sequoia 15.4 through improved state management. The CVSS v3.1 base score is 9.8, indicating a critical severity with network attack vector, low attack complexity, no privileges or user interaction required, and high impact on confidentiality, integrity, and availability. The CWE associated is CWE-346, which relates to improper authorization. No known exploits are reported in the wild yet, but the potential impact is significant given the widespread use of Apple mobile devices and the critical nature of the vulnerability.

For European organizations, the impact of this vulnerability can be substantial. Many enterprises and government agencies rely on iOS and iPadOS devices for daily operations, secure communications, and access to sensitive data. A successful SOP bypass could allow attackers to steal confidential information such as credentials, corporate emails, or proprietary data by tricking users into visiting malicious websites. This could lead to data breaches, financial losses, reputational damage, and regulatory penalties under GDPR due to unauthorized data exposure. Furthermore, the integrity and availability of web applications accessed via Safari on these devices could be compromised, potentially disrupting business processes. The vulnerability’s exploitation does not require user interaction or authentication, increasing the risk of automated or drive-by attacks. Given the criticality and ease of exploitation, European organizations with mobile workforces or BYOD policies using Apple devices are at heightened risk.

To mitigate this vulnerability, European organizations should prioritize updating all Apple devices to iOS 18.4, iPadOS 18.4, or later versions as soon as possible. Enforce strict update policies and verify compliance across the device fleet. Implement network-level protections such as web filtering to block access to known malicious websites and employ DNS filtering to prevent connections to suspicious domains. Use Mobile Device Management (MDM) solutions to monitor device patch status and restrict installation of untrusted applications or profiles. Educate users about the risks of visiting untrusted websites and encourage cautious browsing behavior. Additionally, organizations should audit web applications for potential reliance on SOP enforcement and consider implementing Content Security Policy (CSP) headers to add defense-in-depth. Monitoring network traffic for unusual patterns indicative of SOP bypass exploitation attempts can also aid early detection. Finally, coordinate with incident response teams to prepare for potential exploitation scenarios.