CVE-2025-43503 is a vulnerability identified in Apple Safari and associated Apple operating systems (watchOS, iOS, iPadOS, visionOS) that allows user interface (UI) spoofing due to inconsistent state management within the browser. This flaw enables a malicious website to manipulate the browser's UI elements, potentially displaying deceptive prompts or dialogs that appear legitimate to the user. Such spoofed interfaces can trick users into divulging sensitive information, such as credentials or personal data, or performing unintended actions under false pretenses. The vulnerability stems from improper synchronization of UI states, which attackers can exploit by crafting malicious web content that triggers these inconsistencies. The issue affects Safari versions prior to 26.1 and OS versions before 26.1, with patches released in these versions to correct the state management logic. No CVSS score has been assigned yet, and no active exploitation has been reported, but the nature of UI spoofing vulnerabilities typically makes them attractive for phishing and social engineering attacks. The vulnerability does not require user authentication but does require user interaction (visiting a malicious website). The scope includes all users of vulnerable Apple devices running affected software versions. The fix involves updating to watchOS 26.1, iOS 26.1, iPadOS 26.1, Safari 26.1, and visionOS 26.1, which implement improved UI state management to prevent spoofing. Organizations relying on Apple devices should prioritize patching and educate users on recognizing suspicious UI behavior to mitigate risks.

For European organizations, this vulnerability poses a significant risk to confidentiality and user trust. User interface spoofing can facilitate phishing attacks, leading to credential theft, unauthorized access, and potential data breaches. Organizations with employees using Apple devices and Safari browsers are vulnerable to targeted attacks that exploit this flaw to deceive users into revealing sensitive information or executing harmful actions. The impact extends to sectors handling sensitive data such as finance, healthcare, and government, where compromised credentials can lead to severe operational disruption and regulatory penalties under GDPR. Additionally, the spoofing could undermine trust in digital communications and internal systems if attackers impersonate legitimate interfaces. Although availability and integrity impacts are limited, the potential for social engineering and data compromise is substantial. The lack of known exploits currently provides a window for proactive mitigation, but the ease of exploitation via malicious websites makes timely patching critical. Organizations with remote or mobile workforces using Apple devices are particularly at risk due to increased exposure to web-based threats.

European organizations should implement the following specific mitigation measures: 1) Immediately update all Apple devices to watchOS 26.1, iOS 26.1, iPadOS 26.1, Safari 26.1, and visionOS 26.1 to apply the patch addressing the UI spoofing vulnerability. 2) Enforce strict update policies and automated patch management for Apple ecosystems to ensure timely deployment of security fixes. 3) Conduct targeted user awareness training focused on recognizing suspicious browser dialogs and phishing attempts, emphasizing caution when interacting with unexpected prompts. 4) Employ web filtering and DNS security solutions to block access to known malicious websites and reduce exposure to exploit attempts. 5) Utilize endpoint detection and response (EDR) tools capable of monitoring browser behavior anomalies indicative of UI spoofing or phishing attacks. 6) Implement multi-factor authentication (MFA) across critical systems to mitigate the impact of credential theft resulting from spoofing. 7) Regularly audit and monitor network traffic for unusual patterns that may indicate exploitation attempts. 8) Coordinate with Apple support and security advisories to stay informed about any emerging threats or additional patches related to this vulnerability.