CVE-2025-43424 is a vulnerability identified in Apple iOS and iPadOS that allows a malicious Human Interface Device (HID) to cause an unexpected process crash. The root cause is a lack of proper bounds checking when processing input from HID devices, classified under CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer). This flaw can be exploited by physically connecting a malicious HID device, such as a specially crafted keyboard or mouse, to an affected device. The malicious device can send malformed input that triggers a buffer over-read or buffer overflow condition, leading to a denial-of-service (DoS) by crashing a system process. The vulnerability does not allow for privilege escalation, code execution, or data leakage, as it impacts availability only. No authentication or user interaction is required beyond connecting the device. Apple addressed this issue by improving bounds checks in the affected code paths and released patches in iOS 26.1, iPadOS 26.1, and macOS Tahoe 26.1. There are no reports of active exploitation in the wild. The CVSS v3.1 base score is 6.5, reflecting a medium severity level with attack vector as adjacent network (physically local), low attack complexity, no privileges or user interaction needed, and impact limited to availability.

The primary impact of CVE-2025-43424 is denial-of-service through unexpected process crashes on Apple iOS and iPadOS devices. This can disrupt normal device operation, potentially causing application failures or system instability. For organizations relying on iOS/iPadOS devices for critical communications or operations, such disruptions could affect productivity and service availability. While the vulnerability does not compromise confidentiality or integrity, repeated exploitation could degrade user experience and trust in device reliability. The requirement for physical access to connect a malicious HID device limits remote exploitation risk but raises concerns in environments with shared or publicly accessible devices. Attackers with physical access could leverage this to cause targeted disruptions, especially in high-security or sensitive environments. The absence of known exploits in the wild reduces immediate risk but does not eliminate the threat, especially as patches are not yet universally deployed.

To mitigate CVE-2025-43424, organizations should prioritize updating all affected Apple devices to iOS 26.1, iPadOS 26.1, or macOS Tahoe 26.1 or later, where the vulnerability is patched. Physical security controls should be enhanced to prevent unauthorized connection of external HID devices, including restricting USB ports or using endpoint security solutions that monitor and control peripheral device connections. Device management policies can enforce restrictions on device pairing and USB accessory usage. Educating users about the risks of connecting untrusted peripherals can reduce accidental exposure. For high-security environments, consider disabling unused physical ports or employing hardware-based port blockers. Monitoring system logs for unusual device connection events and process crashes can provide early detection of attempted exploitation. Regular vulnerability scanning and patch management processes should be maintained to ensure timely remediation.