Home/CVE/This issue was addressed with improved checks. This issue is fixed in macOS Big Sur 11.2, Security Update 2021-001 Catal
CVE

CVE-2021-1771

This issue was addressed with improved checks. This issue is fixed in macOS Big Sur 11.2, Security Update 2021-001 Catal

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.

LOW · CVSS 3.3 EPSS 0.00238
Monitor
  • No active-exploitation, high-EPSS, or public-exploit signals - routine patching cadence
Sigma rules8 YARA rules0
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Affected Products & Versions

4
apple mac os x>= 10.14 and < 10.14.6
apple mac os x>= 10.15 and < 10.15.7
apple mac os xall versions
apple macos>= 11.0 and < 11.2
◈

Sigma Hunt Rules

8
Exact rules name this CVE ID. Product rules name an affected product in their title. Related rules cover techniques used by actors who exploited this CVE. Showing the most relevant matches; the complete related set is on the full drill-down.
producthighSuspicious Microsoft Office Child Process - MacOS
producthighRemote Access Tool - Renamed MeshAgent Execution - MacOS
producthighBinary Padding - MacOS
productmediumSuspicious Execution via macOS Script Editor
productmediumSystem Information Discovery Via Sysctl - MacOS
productmediumNew File Exclusion Added To Time Machine Via Tmutil - MacOS
▣

Scoring & Timeline

3.3
LOW · CVSS v3.1 · product-security@apple.com
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD02 Apr 2021 · 06:15 PM
CVSS VectorCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
🔗

References & Sources

1
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://support.apple.com/en-us/HT212147Release NotesVendor Advisory
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