CVE-2021-21779: Use After Free

Published May 24, 2021
·
Updated

A use-after-free vulnerability exists in the way that WebKit GraphicsContext handles certain events. A specially crafted web page can lead to a potential information leak and further memory corruption. A victim must be tricked into visiting a malicious web page to trigger this vulnerability.

Other sources

A use-after-free vulnerability exists in the way Webkit’s GraphicsContext handles certain events in WebKitGTK 2.30.4. A specially crafted web page can lead to a potential information leak and further memory corruption. A victim must be tricked into visiting a malicious web page to trigger this vulnerability.

WebKit. A use after free issue was addressed with improved memory management.

Credit

Marcin Towalski(Cisco Talos), Marcin Towalski(Cisco Talos), Marcin Towalski(Cisco Talos), Marcin Towalski(Cisco Talos), Marcin Towalski(Cisco Talos)

Affected Software

13 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
WebKitGTK WebKitGTK=2.30.4
Fedoraproject Fedora=33
Fedoraproject Fedora=34
Debian Debian Linux=10.0
Apple iOS<14.6
14.6
Apple iPadOS<14.6
14.6
redhat/webkitgtk<2.32.3
2.32.3

Event History

Jul 8, 2021
CVE Published
via MITRE·11:21 AM
Data Sourced
via MITRE·11:21 AM
DescriptionSeverityWeakness
Jul 28, 2021
Data Sourced
via Red Hat·01:34 PM
DescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is CVE-2021-21779?

CVE-2021-21779 is a vulnerability in WebKit that allows for a use after free issue due to a memory management flaw.

2

What software is affected by CVE-2021-21779?

CVE-2021-21779 affects Apple tvOS versions up to and exclusive of 14.6, Apple watchOS versions up to and exclusive of 7.5, Apple Safari versions up to and exclusive of 14.1.1, Apple macOS Big Sur versions up to and exclusive of 11.4, Apple iOS versions up to and exclusive of 14.6, and Apple iPadOS versions up to and exclusive of 14.6.

3

How can the use after free issue in CVE-2021-21779 be fixed?

To fix the use after free issue in CVE-2021-21779, update to the latest version of the affected software.

4

Where can I find more information about CVE-2021-21779?

More information about CVE-2021-21779 can be found on the Apple support website at the following links: [link1], [link2], [link3].

5

What is CWE-416?

CWE-416 is a common weakness enumeration reference for use after free vulnerabilities.

Contact

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