CVE-2021-30818: High severity Apple Safari vulnerability

Published Sep 13, 2021
·
Updated

A flaw was found in WebKitGTK. A type confusion issue was addressed with improved state handling.

References: https://webkitgtk.org/security/WSA-2021-0007.html https://www.openwall.com/lists/oss-security/2021/12/20/6

Other sources

A type confusion issue was addressed with improved state handling. This issue is fixed in iOS 14.8 and iPadOS 14.8, tvOS 15, iOS 15 and iPadOS 15, Safari 15, watchOS 8. Processing maliciously crafted web content may lead to arbitrary code execution.

WebKit. A type confusion issue was addressed with improved state handling.

Credit

Amar Menezes@@amarekano(Zon8Research)

Affected Software

20 affected componentsFixes available
Apple Safari<15.0
Apple iPadOS<14.8
Apple iPhone OS<14.8
Apple macOS<12.0.1
Apple tvOS<15.0
Apple WatchOS<8.0
Apple tvOS<15
15
Apple WatchOS<8
8
Apple macOS Monterey<12.0.1
12.0.1
Apple Safari<15
15
Apple iOS<14.8
14.8
Apple iPadOS<14.8
14.8
Apple iOS<15
15
Apple iPadOS<15
15
redhat/webkitgtk<2.34.0
2.34.0
alpine/webkit2gtk<2.34.0-r0
2.34.0-r0
alpine/webkit2gtk<2.34.0-r0
2.34.0-r0
alpine/webkit2gtk<2.34.0-r0
2.34.0-r0
alpine/webkit2gtk<2.34.0-r0
2.34.0-r0
alpine/webkit2gtk<2.34.0-r0
2.34.0-r0

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade tvOS to a version that resolves this vulnerability.

    Fixed in 15
  2. Upgrade

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

    Fixed in 8
  3. Upgrade

    Upgrade macOS to a version that resolves this vulnerability.

    Fixed in 12.0.1
  4. Upgrade

    Upgrade Safari to a version that resolves this vulnerability.

    Fixed in 15
  5. Upgrade

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

    Fixed in 14.8
  6. Upgrade

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

    Fixed in 14.8
  7. Upgrade

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

    Fixed in 15
  8. Upgrade

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

    Fixed in 15
  9. Upgrade

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

    Fixed in 2.34.0
  10. Upgrade

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

    Fixed in 2.34.0-r0
  11. Upgrade

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

    Fixed in 14.8
  12. Upgrade

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

    Fixed in 15
  13. Upgrade

    Upgrade tvOS and Safari to a version that resolves this vulnerability.

    Fixed in 15
  14. Upgrade

    Upgrade watchOS to a version that resolves this vulnerability.

    Fixed in 8

Event History

Oct 28, 2021
CVE Published
via MITRE·06:17 PM
Data Sourced
via MITRE·06:17 PM
DescriptionWeakness
Data Sourced
via NVD·07:15 PM
DescriptionSeverityWeaknessAffected Software
Data Sourced
via OSV·07:15 PM
DescriptionSeverityAffected Software
Dec 20, 2021
Data Sourced
via Red Hat·07:07 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-2021-30818?

CVE-2021-30818 is a type confusion issue in WebKit that has been addressed with improved state handling.

2

Which software versions are affected by CVE-2021-30818?

CVE-2021-30818 affects watchOS up to version 8, iOS up to version 15, iPadOS up to version 15, iOS up to version 14.8, iPadOS up to version 14.8, tvOS up to version 15, Safari up to version 15, and macOS Monterey up to version 12.0.1.

3

How can I fix the vulnerability in my software?

To fix the vulnerability, update your software to the latest version provided by Apple.

4

Where can I find more information about CVE-2021-30818?

You can find more information about CVE-2021-30818 on the Apple support website.

Company

Resources

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