The issue was addressed with improved deletion. This issue is fixed in macOS Big Sur 11.0.1, watchOS 7.0, iOS 14.0 and iPadOS 14.0. A local user may be able to discover a user’s deleted messages.
http://seclists.org/fulldisclosure/2020/Dec/32
https://support.apple.com/en-us/HT211844
Source: MITRE
Published: 2020-12-08
Updated: 2021-03-11
Type: NVD-CWE-noinfo
Base Score: 2.1
Vector: AV:L/AC:L/Au:N/C:P/I:N/A:N
Impact Score: 2.9
Exploitability Score: 3.9
Severity: LOW
Base Score: 5.5
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Impact Score: 3.6
Exploitability Score: 1.8
Severity: MEDIUM