CVE-2026-20645 is a vulnerability identified in Apple’s iOS and iPadOS operating systems, stemming from an inconsistent user interface (UI) state management issue classified under CWE-1021 (Improper Restriction of Rendered UI Layers or Frames). This flaw allows an attacker with physical access to a locked device to bypass certain UI restrictions and view sensitive user information without requiring authentication or user interaction. The vulnerability does not permit modification or deletion of data (integrity unaffected) nor does it impact device availability. The root cause involves improper handling of UI states that leads to exposure of sensitive data on the lock screen or through UI elements that should be inaccessible when the device is locked. Apple addressed this issue in iOS 26.3 and iPadOS 26.3, as well as in iOS 18.7.5 and iPadOS 18.7.5, by improving state management to ensure sensitive information is properly concealed when the device is locked. The CVSS v3.1 base score is 4.6, indicating a medium severity level, with attack vector being physical access (AV:P), low attack complexity (AC:L), no privileges required (PR:N), no user interaction (UI:N), unchanged scope (S:U), high confidentiality impact (C:H), and no impact on integrity or availability (I:N/A:N). No known exploits have been reported in the wild to date, but the vulnerability remains a concern especially in environments where devices may be lost or stolen.

The primary impact of CVE-2026-20645 is the unauthorized disclosure of sensitive user information on locked Apple iOS and iPadOS devices. This can lead to privacy breaches, exposure of personal or corporate data, and potential secondary attacks leveraging the disclosed information. Organizations using Apple mobile devices for sensitive communications or data storage face increased risk if devices are physically compromised. Although the vulnerability does not allow data modification or denial of service, the confidentiality breach alone can undermine trust and compliance with data protection regulations. The risk is heightened in sectors such as government, finance, healthcare, and enterprises with mobile workforce, where device theft or loss is a realistic threat. The absence of required authentication or user interaction makes exploitation straightforward for anyone with physical access, increasing the likelihood of data leakage in uncontrolled environments.

To mitigate CVE-2026-20645, organizations and users should promptly update affected devices to iOS 26.3, iPadOS 26.3, or the respective 18.7.5 versions where the vulnerability is patched. Beyond patching, enforcing strong physical security controls to prevent unauthorized access to devices is critical, including use of secure storage, device tracking, and remote wipe capabilities. Implementing additional device management policies such as disabling lock screen notifications that may reveal sensitive information can reduce exposure. Organizations should also educate users about the risks of leaving devices unattended and encourage use of strong passcodes and biometric locks. For high-risk environments, consider deploying Mobile Device Management (MDM) solutions that can enforce security configurations and monitor device compliance. Regular audits of device security posture and incident response plans for lost or stolen devices will further reduce potential impact.