CVE-2025-43427 is a vulnerability identified in Apple Safari and related Apple operating systems (iOS, iPadOS, macOS, tvOS, visionOS) prior to version 26.1. The root cause is improper state management when processing web content, which can be maliciously crafted to trigger an unexpected process crash. This vulnerability is classified under CWE-20 (Improper Input Validation) and CWE-703 (Improper Check or Handling of Exceptional Conditions). The impact is limited to availability, as the crash results in denial of service by terminating the Safari process unexpectedly. The CVSS v3.1 base score is 4.3 (medium severity), reflecting that the attack vector is network-based (remote), requires no privileges, but does require user interaction (visiting a malicious webpage). The scope is unchanged, meaning the vulnerability affects only the targeted process without escalating privileges or affecting other system components. No known exploits have been reported in the wild, but the vulnerability could be leveraged by attackers to disrupt user sessions or cause service interruptions. Apple addressed the issue by improving state management in the affected components, releasing patches in version 26.1 of Safari and the corresponding OS updates. The vulnerability affects all versions prior to these patches, but specific affected versions are unspecified. Given the widespread use of Apple devices and Safari in enterprise and consumer environments, this vulnerability poses a risk primarily of denial of service through process crashes triggered by malicious web content.

For European organizations, the primary impact of CVE-2025-43427 is denial of service through unexpected crashes of Safari processes. This can disrupt business operations relying on Safari for web-based applications, internal portals, or cloud services accessed via Safari on Apple devices. Organizations with large deployments of Apple hardware (MacBooks, iPhones, iPads) and those using Safari as a default browser may experience productivity loss and potential operational delays. While the vulnerability does not compromise confidentiality or integrity, repeated crashes could be exploited to degrade service availability or as part of a broader attack chain to distract or disrupt security monitoring. Sectors such as finance, healthcare, government, and critical infrastructure in Europe that depend on Apple ecosystems for secure communications and workflows are particularly sensitive to availability disruptions. Additionally, remote workers using Apple devices may be vulnerable if they access untrusted or compromised websites. The lack of known exploits reduces immediate risk, but the medium severity rating and ease of triggering the crash via web content necessitate timely patching to maintain operational stability.

European organizations should prioritize deploying the Apple security updates that include Safari 26.1 and the corresponding OS updates (iOS, iPadOS, macOS, tvOS, visionOS 26.1) to all managed Apple devices. Patch management processes must ensure rapid identification and remediation of vulnerable systems. Network security controls should be enhanced to restrict access to untrusted or suspicious web content, including the use of web filtering and DNS filtering solutions. Endpoint protection platforms can be configured to monitor and alert on abnormal Safari process terminations to detect potential exploitation attempts. User awareness training should emphasize caution when clicking links or visiting unfamiliar websites, especially on Apple devices. For critical environments, consider deploying alternative browsers temporarily or sandboxing Safari processes to limit impact. Regular vulnerability scanning and compliance checks should verify that all Apple devices are updated. Finally, incident response plans should include procedures for handling denial of service incidents caused by browser crashes to minimize operational disruption.