CVE-2020-9977

Name: CVE-2020-9977
Creator: NVD / NIST
Published: 2020-12-08T20:15:17.73+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.5/10EPSS 0.91%

Last modified Jun 17, 2026

CVE-2020-9977 is a medium-severity vulnerability rated 5.5/10 on the CVSS scale. A validation issue existed in the entitlement verification. This issue was addressed with improved validation of the process entitlement. EPSS estimates a 0.91% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1

5.5/10

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

EPSS Probability

0.91%

55.6th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-20

Affected Software

Vendor	Product	Versions
Apple	Ipados	< 14.2
Apple	Iphone Os	< 14.2
Apple	Mac Os X	< 11.0.1

References

http://seclists.org/fulldisclosure/2020/Dec/32Mailing List, Third Party Advisory
https://support.apple.com/en-us/HT211850Vendor Advisory
https://support.apple.com/en-us/HT211931Vendor Advisory
http://seclists.org/fulldisclosure/2020/Dec/32Mailing List, Third Party Advisory
https://support.apple.com/en-us/HT211850Vendor Advisory
https://support.apple.com/en-us/HT211931Vendor Advisory

Timeline

Published: Dec 8, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-9977?

How severe is CVE-2020-9977?

CVE-2020-9977 has a CVSS score of 5.5/10 (MEDIUM severity). The EPSS model estimates a 0.91% probability of exploitation in the next 30 days.

How do I fix CVE-2020-9977?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-9977?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST