CVE-2025-43438 is a use-after-free vulnerability identified in Apple Safari, affecting multiple Apple operating systems including watchOS 26.1, macOS Tahoe 26.1, iOS 26.1, iPadOS 26.1, Safari 26.1, iOS 18.7.2, iPadOS 18.7.2, and visionOS 26.1. The vulnerability arises from improper memory management when processing specially crafted web content, leading to a use-after-free condition (CWE-416). This flaw can cause Safari to crash unexpectedly, resulting in a denial-of-service scenario. The vulnerability does not compromise confidentiality or integrity but impacts availability. Exploitation requires no privileges but does require user interaction, such as visiting a malicious website. The CVSS v3.1 base score is 4.3 (medium), with attack vector network (AV:N), low attack complexity (AC:L), no privileges required (PR:N), user interaction required (UI:R), unchanged scope (S:U), no confidentiality or integrity impact (C:N/I:N), and low availability impact (A:L). Apple has fixed the issue by improving memory management in the affected Safari and OS versions. No known exploits are reported in the wild, but the vulnerability could be leveraged in targeted denial-of-service attacks or as part of multi-stage exploits. Organizations using Apple devices with Safari should apply the patches promptly to mitigate potential disruptions.

For European organizations, this vulnerability primarily poses a risk of denial-of-service through unexpected Safari crashes when users access malicious web content. This can disrupt business operations, especially in sectors relying heavily on web-based applications and Safari as a primary browser, such as finance, government, and technology. While the vulnerability does not allow data theft or system compromise directly, repeated crashes could degrade user productivity and potentially be used as a vector in broader attack campaigns. Enterprises with remote or mobile workforces using Apple devices are particularly at risk. The lack of known exploits reduces immediate threat but does not eliminate the risk of future exploitation. Unpatched systems remain vulnerable to targeted attacks leveraging this flaw to cause service interruptions or user frustration. The impact on availability can affect critical services, customer-facing portals, and internal workflows dependent on Safari.

European organizations should prioritize updating all Apple devices to the patched versions: watchOS 26.1, macOS Tahoe 26.1, iOS 26.1, iPadOS 26.1, Safari 26.1, iOS 18.7.2, iPadOS 18.7.2, and visionOS 26.1. Implement strict web filtering and URL reputation services to block access to known malicious sites that could exploit this vulnerability. Educate users about the risks of visiting untrusted websites and the importance of applying updates promptly. Employ endpoint detection and response (EDR) solutions to monitor for abnormal Safari crashes or suspicious web activity. Consider deploying network-level protections such as DNS filtering and secure web gateways to reduce exposure. Regularly audit and inventory Apple devices to ensure compliance with patch management policies. For high-risk environments, temporarily restricting Safari usage or enforcing alternative browsers until patches are applied may be warranted. Maintain backups and incident response plans to address potential denial-of-service impacts.