CVE-2026-20627: 
macOS vulnerability analysis and mitigation

CVE-2026-20627 is an improper input validation vulnerability in Apple's CoreServices component related to the handling of environment variables. A malicious app may exploit this flaw to access sensitive user data without authorization. It affects iOS and iPadOS (before 26.3), macOS Sonoma (14.0–14.8.4), macOS Tahoe (before 26.3), visionOS (before 26.3), and watchOS (before 26.3). The vulnerability was disclosed and patched on February 11, 2026, and was reported by an anonymous researcher. It carries a CVSS v3.1 base score of 5.5 (Medium) (Apple iOS/iPadOS Advisory, Apple macOS Tahoe Advisory).

The vulnerability is classified as CWE-20 (Improper Input Validation) and resides in the CoreServices component's handling of environment variables across Apple platforms. Insufficient validation of environment variable inputs allows a locally installed app to read sensitive user data that should be inaccessible to it. Exploitation requires user interaction (e.g., running a malicious app) and is limited to local access, with no network-based attack vector. Apple addressed the issue with improved validation logic in the affected component (Apple iOS/iPadOS Advisory, Apple macOS Sonoma Advisory, Apple watchOS Advisory).

Successful exploitation allows a malicious app to access sensitive user data that it would not normally be permitted to read, resulting in a high confidentiality impact. There is no integrity or availability impact associated with this vulnerability. The scope is limited to the local device; however, exposure of sensitive user data (such as personal information, credentials, or private files accessible via environment variable manipulation) could facilitate further attacks or privacy violations (Apple macOS Tahoe Advisory, Apple visionOS Advisory).

Apple has released patches addressing CVE-2026-20627 in the following updates: iOS 26.3 and iPadOS 26.3, macOS Sonoma 14.8.4, macOS Tahoe 26.3, visionOS 26.3, and watchOS 26.3 — all released February 11, 2026. Users should update their devices to these versions or later as soon as possible. No configuration-based workarounds have been published; updating to the patched OS version is the only recommended remediation (Apple iOS/iPadOS Advisory, Apple macOS Sonoma Advisory, Apple macOS Tahoe Advisory, Apple watchOS Advisory, Apple visionOS Advisory).