CVE-2025-43355 is a type confusion vulnerability classified under CWE-843 that affects Apple’s iOS, iPadOS, macOS, tvOS, visionOS, and watchOS platforms. The vulnerability stems from improper memory handling that leads to type confusion, a condition where a program mistakenly treats a piece of memory as a different type than it actually is. This can cause unpredictable behavior, including crashes or denial-of-service conditions. The flaw can be triggered by a malicious app running on the device, which does not require any special privileges but does require user interaction to execute the exploit. The vulnerability was addressed by Apple in updates iOS 18.7, iPadOS 18.7, iOS 26, iPadOS 26, macOS Sequoia 15.7, macOS Sonoma 14.8, macOS Tahoe 26, tvOS 26, visionOS 26, and watchOS 26 through improved memory handling techniques that prevent the type confusion from occurring. The CVSS v3.1 base score is 5.5, indicating a medium severity level, with the vector AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H, meaning the attack requires local access and user interaction but no privileges, and impacts availability only. There are no known exploits in the wild at the time of publication, but the vulnerability poses a risk of denial-of-service attacks that could disrupt device functionality or critical applications running on these platforms.

The primary impact of CVE-2025-43355 is denial-of-service, which can disrupt the availability of Apple devices and the applications running on them. For organizations relying heavily on Apple hardware and software ecosystems, such as enterprises using iPhones, iPads, or Macs for business-critical operations, this could lead to productivity loss, interrupted communications, and potential operational downtime. While the vulnerability does not affect confidentiality or integrity, the availability impact can be significant in environments where device uptime is critical, such as healthcare, finance, or emergency services. The requirement for local access and user interaction limits the attack surface, reducing the likelihood of widespread remote exploitation. However, targeted attacks via malicious apps or social engineering could still pose a threat. The absence of known exploits in the wild currently reduces immediate risk but does not eliminate the potential for future exploitation once the vulnerability becomes more widely known.

To mitigate CVE-2025-43355, organizations should: 1) Prioritize deploying the latest Apple OS updates that include the fix (iOS/iPadOS 18.7 and 26, macOS Sequoia 15.7, Sonoma 14.8, Tahoe 26, tvOS 26, visionOS 26, watchOS 26). 2) Enforce strict app installation policies, allowing only apps from trusted sources such as the Apple App Store to reduce the risk of malicious apps exploiting this vulnerability. 3) Educate users about the risks of installing untrusted applications and the importance of user interaction in triggering the exploit. 4) Implement mobile device management (MDM) solutions to monitor and control app installations and OS versions across the device fleet. 5) Regularly audit devices for compliance with patch levels and remove or quarantine devices that cannot be updated promptly. 6) Monitor device logs and behavior for signs of crashes or abnormal activity that could indicate exploitation attempts. 7) For high-security environments, consider restricting local access to devices and enforcing strong authentication to reduce the risk of unauthorized physical or local access.