CVE-2020-9977

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.9% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-12-08 · updated 2026-06-17
Weakness: CWE-20

Description

A validation issue existed in the entitlement verification. This issue was addressed with improved validation of the process entitlement. This issue is fixed in macOS Big Sur 11.0.1, iOS 14.0 and iPadOS 14.0. A malicious application may be able to determine a user's open tabs in Safari.

Affected products

Apple iPadOS: before 14.2 — fixed in 14.2
Apple Iphone Os: before 14.2 — fixed in 14.2
macOS: before 11.0.1 — fixed in 11.0.1

How to fix

Upgrade to a fixed version: Apple iPadOS 14.2; Apple Iphone Os 14.2; macOS 11.0.1. Check the vendor advisory for mitigations.

References

http://seclists.org/fulldisclosure/2020/Dec/32
https://support.apple.com/en-us/HT211850
https://support.apple.com/en-us/HT211931
http://seclists.org/fulldisclosure/2020/Dec/32
https://support.apple.com/en-us/HT211850
https://support.apple.com/en-us/HT211931

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