CVE-2025-43424 is a vulnerability identified in Apple’s macOS, iOS, and iPadOS operating systems that allows a malicious Human Interface Device (HID) to trigger an unexpected process crash. The root cause is a lack of proper bounds checking in the handling of input from HID devices, which is a classic buffer over-read or buffer overflow issue categorized under CWE-119. This vulnerability can be exploited remotely by connecting a specially crafted malicious HID device, such as a keyboard or mouse, to the target system. Exploitation does not require any prior authentication or user interaction, making it easier for attackers with physical access to cause denial of service. The impact is limited to availability, as the vulnerability causes process crashes without compromising confidentiality or integrity of data. Apple has fixed this issue by implementing improved bounds checks in macOS Tahoe 26.1, iOS 26.1, and iPadOS 26.1. No public exploits or active attacks have been reported to date, but the vulnerability’s medium CVSS score of 6.5 reflects the ease of exploitation and potential disruption. The vulnerability affects unspecified versions prior to these patched releases, so users running older versions remain at risk. This vulnerability highlights the risks posed by malicious peripherals in environments where physical device security is not tightly controlled.

The primary impact of CVE-2025-43424 is denial of service through unexpected process crashes caused by malicious HID devices. Organizations relying on Apple devices, especially in environments where physical access to systems is possible, may experience service disruptions or system instability. This can affect endpoint availability, interrupt user workflows, and potentially impact critical operations if the affected processes are essential system or application components. While confidentiality and integrity are not directly compromised, repeated crashes could lead to broader operational issues or be leveraged as part of a larger attack chain. The vulnerability is particularly concerning in high-security or sensitive environments where device trust is critical, such as government, finance, healthcare, and industrial control systems. The lack of required authentication or user interaction lowers the barrier for exploitation, increasing the risk in scenarios where attackers can connect malicious peripherals physically or via supply chain attacks.

To mitigate CVE-2025-43424, organizations should promptly update all Apple devices to macOS Tahoe 26.1, iOS 26.1, and iPadOS 26.1 or later, where the vulnerability is fixed. Beyond patching, organizations should enforce strict physical security controls to prevent unauthorized access to USB ports and other HID interfaces. Deploy endpoint protection solutions capable of monitoring and restricting unknown or untrusted peripheral devices. Implement device whitelisting policies to allow only approved HID devices. Regularly audit connected peripherals and educate users about the risks of connecting unknown devices. In high-risk environments, consider disabling unused HID interfaces or using hardware-based port blockers. Monitoring system logs for unusual process crashes related to HID input can help detect exploitation attempts. Finally, integrate these controls into broader supply chain security practices to reduce the risk of malicious devices entering the environment.