CVE-2021-1781
A privacy issue existed in the handling of Contact cards. This was addressed with improved state management. This issue is fixed in macOS Big Sur 11.2, Security Update 2021-001 Catalina, Security Update 2021-001 Mojave, iOS 14.4 and iPadOS 14.4. A malicious application may be able to leak sensitive user information.
Source: CVE-2021-1781