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CVE

CVE-2021-30855

A validation issue existed in the handling of symlinks. This issue was addressed with improved validation of symlinks. T

A validation issue existed in the handling of symlinks. This issue was addressed with improved validation of symlinks. This issue is fixed in Security Update 2021-005 Catalina, iOS 14.8 and iPadOS 14.8, iOS 15 and iPadOS 15, watchOS 8, macOS Big Sur 11.6.

An application may be able to access restricted files.

MEDIUM · CVSS 5.5 EPSS 0.00214
Monitor
  • No active-exploitation, high-EPSS, or public-exploit signals - routine patching cadence
Sigma rules8 YARA rules0
⬡

Weakness Classification

CWE-59Improper Link Resolution Before File Access ('Link Following')
▤

Affected Products & Versions

7
apple ipados< 14.8
apple iphone os< 14.8
apple mac os x< 10.15.7
apple mac os xall versions
apple macos< 11.6
apple tvos< 15.0
apple watchos< 8.0
◈

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

5.5
MEDIUM · 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 NVD24 Aug 2021 · 07:15 PM
CVSS VectorCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
🔗

References & Sources

6
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/HT212804
https://support.apple.com/en-us/HT212805
https://support.apple.com/en-us/HT212807
https://support.apple.com/en-us/HT212814
https://support.apple.com/en-us/HT212819
https://support.apple.com/kb/HT212815
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