CVE-2021-30720: Medium severity Apple macOS Big Sur vulnerability

Published May 24, 2021
·
Updated

A logic issue was addressed with improved restrictions.

Credit

David Schütz@@xdavidhu, David Schütz@@xdavidhu, David Schütz@@xdavidhu, David Schütz@@xdavidhu, David Schütz@@xdavidhu

Affected Software

22 affected componentsFixes available
debian/webkit2gtk
2.36.4-1~deb10u12.38.6-0+deb10u12.40.5-1~deb11u12.42.1-1~deb11u22.40.5-1~deb12u12.42.1-1~deb12u12.42.1-2
debian/wpewebkit
2.38.6-1~deb11u12.38.6-12.42.1-1
Apple macOS Big Sur<11.4
11.4
Apple tvOS<14.6
14.6
Apple WatchOS<7.5
7.5
Apple Safari<14.1.1
14.1.1
Apple iOS<14.6
14.6
Apple iPadOS<14.6
14.6
Apple Safari<14.1.1
Apple iPadOS<14.6
Apple iPhone OS<14.6
Apple macOS>=11.0.1<11.4
Apple tvOS<14.6
Apple WatchOS<7.5
redhat/webkitgtk<2.32.3
2.32.3
alpine/webkit2gtk<2.32.3-r0
2.32.3-r0
alpine/webkit2gtk<2.32.3-r0
2.32.3-r0
alpine/webkit2gtk<2.32.3-r0
2.32.3-r0
alpine/webkit2gtk<2.32.3-r0
2.32.3-r0
alpine/webkit2gtk<2.32.3-r0
2.32.3-r0
alpine/webkit2gtk<2.32.3-r0
2.32.3-r0
alpine/webkit2gtk<2.32.3-r0
2.32.3-r0

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade debian/webkit2gtk to a version that resolves this vulnerability.

    Fixed in 2.36.4-1~deb10u1Fixed in 2.38.6-0+deb10u1Fixed in 2.40.5-1~deb11u1Fixed in 2.42.1-1~deb11u2Fixed in 2.40.5-1~deb12u1Fixed in 2.42.1-1~deb12u1Fixed in 2.42.1-2
  2. Upgrade

    Upgrade debian/wpewebkit to a version that resolves this vulnerability.

    Fixed in 2.38.6-1~deb11u1Fixed in 2.38.6-1Fixed in 2.42.1-1
  3. Upgrade

    Upgrade Apple macOS to a version that resolves this vulnerability.

    Fixed in 11.4
  4. Upgrade

    Upgrade tvOS to a version that resolves this vulnerability.

    Fixed in 14.6
  5. Upgrade

    Upgrade Apple iOS, iPadOS, and watchOS to a version that resolves this vulnerability.

    Fixed in 7.5
  6. Upgrade

    Upgrade Safari to a version that resolves this vulnerability.

    Fixed in 14.1.1
  7. Upgrade

    Upgrade Apple iOS and iPadOS to a version that resolves this vulnerability.

    Fixed in 14.6
  8. Upgrade

    Upgrade Apple iOS, iPadOS, and macOS to a version that resolves this vulnerability.

    Fixed in 14.6
  9. Upgrade

    Upgrade redhat/webkitgtk to a version that resolves this vulnerability.

    Fixed in 2.32.3
  10. Upgrade

    Upgrade alpine/webkit2gtk to a version that resolves this vulnerability.

    Fixed in 2.32.3-r0
  11. Upgrade

    Upgrade iOS to a version that resolves this vulnerability.

    Fixed in 14.6
  12. Upgrade

    Upgrade iPadOS to a version that resolves this vulnerability.

    Fixed in 14.6
  13. Upgrade

    Upgrade macOS Big Sur to a version that resolves this vulnerability.

    Fixed in 11.4
  14. Upgrade

    Upgrade watchOS to a version that resolves this vulnerability.

    Fixed in 7.5

Event History

Jul 28, 2021
Data Sourced
via Red Hat·01:41 PM
DescriptionSeverityAffected Software
Sep 8, 2021
CVE Published
via MITRE·01:41 PM
Data Sourced
via MITRE·01:41 PM
DescriptionWeakness
Data Sourced
via NVD·02:15 PM
DescriptionSeverityWeaknessAffected Software
Data Sourced
via OSV·02:15 PM
DescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

Frequently Asked Questions

1

What is CVE-2021-30720?

CVE-2021-30720 is a logic issue in WebKit that has been addressed with improved restrictions.

2

Which software is affected by CVE-2021-30720?

CVE-2021-30720 affects Apple tvOS 14.6, Apple watchOS 7.5, Apple Safari 14.1.1, Apple macOS Big Sur 11.4, Apple iOS 14.6, and Apple iPadOS 14.6.

3

How severe is CVE-2021-30720?

The severity of CVE-2021-30720 is not mentioned in the provided information.

4

How can I fix the vulnerability in CVE-2021-30720?

To fix the vulnerability in CVE-2021-30720, ensure that you have installed the latest updates and patches from Apple for the affected software versions.

5

Where can I find more information about CVE-2021-30720?

You can find more information about CVE-2021-30720 on the Apple support page. Here are the references: [Apple Support - HT212533](https://support.apple.com/en-us/HT212533), [Apple Support - HT212529](https://support.apple.com/en-us/HT212529), [Apple Support - HT212534](https://support.apple.com/en-us/HT212534).

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