CVE-2020-9920

Severity: critical (CVSS 9.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.9% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-10-22 · updated 2026-06-17
Weakness: CWE-22

Description

A path handling issue was addressed with improved validation. This issue is fixed in iOS 13.6 and iPadOS 13.6, macOS Catalina 10.15.6, watchOS 6.2.8. A malicious mail server may overwrite arbitrary mail files.

Affected products

Apple iPadOS: before 13.6 — fixed in 13.6
Apple Iphone Os: before 13.6 — fixed in 13.6
macOS: before 10.15.6 — fixed in 10.15.6
Apple watchOS: before 6.2.8 — fixed in 6.2.8

How to fix

Upgrade to a fixed version: Apple iPadOS 13.6; Apple Iphone Os 13.6; macOS 10.15.6; Apple watchOS 6.2.8. Check the vendor advisory for mitigations.

References

https://support.apple.com/kb/HT211288
https://support.apple.com/kb/HT211289
https://support.apple.com/kb/HT211291
https://support.apple.com/kb/HT211288
https://support.apple.com/kb/HT211289
https://support.apple.com/kb/HT211291

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