CVE-2021-1771

3.3 lowEPSS 0.6%

Low (3.3) in apple. EPSS 0.6% chance of exploitation in the next 30 days.

This issue was addressed with improved checks. This issue is fixed in macOS Big Sur 11.2, Security Update 2021-001 Catalina, Security Update 2021-001 Mojave. A user that is removed from an iMessage group could rejoin the group.

Severity

CVSS 3.1

3.3 low

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N

EPSS: 0.6% chance of exploitation in the next 30 days; higher than 46% of CVEs (scores of 2026-10-31)
Published: 2021-04-02
Modified: 2026-06-17
Record from: the NVD, synced 2026-10-19

Affected

apple:mac_os_x
apple:macos

References

https://support.apple.com/en-us/HT212147
https://support.apple.com/en-us/HT212147

Check your stack JSON