CVE-2021-43535: Use After Free

Published Oct 5, 2021
·
Updated

A use-after-free could have occured when an HTTP2 session object was released on a different thread, leading to memory corruption and a potentially exploitable crash.

Other sources

A use-after-free could have occurred when an HTTP2 session object was released on a different thread, leading to memory corruption and a potentially exploitable crash.

Mozilla

Affected Software

12 affected componentsFixes available
debian/firefox
118.0.2-1
debian/firefox-esr
91.12.0esr-1~deb10u1115.3.1esr-1~deb10u1102.15.0esr-1~deb11u1115.3.1esr-1~deb11u1102.15.1esr-1~deb12u1115.3.0esr-1~deb12u1115.3.0esr-1115.4.0esr-1
debian/thunderbird
1:91.12.0-1~deb10u11:115.3.1-1~deb10u11:102.13.1-1~deb11u11:115.3.1-1~deb11u11:102.15.1-1~deb12u11:115.3.1-1~deb12u11:115.3.1-1
Mozilla Thunderbird<91.3
91.3
Mozilla Firefox<93
93
Mozilla Firefox ESR<91.3
91.3
Mozilla Firefox<93.0
Mozilla Firefox ESR<91.3.0
Mozilla Thunderbird<91.3.0
Debian Debian Linux=9.0
Debian Debian Linux=10.0
Debian Debian Linux=11.0

Event History

Oct 5, 2021
CVE Published
12:00 AM
Data Sourced
via Mozilla·12:00 AM
DescriptionSeverityAffected Software
Nov 2, 2021
Updated
via Mozilla·12:00 AM
Affected Software
Nov 3, 2021
Updated
via Mozilla·12:00 AM
Affected Software
Dec 8, 2021
CVE Published
via MITRE·09:20 PM
Data Sourced
via MITRE·09:20 PM
DescriptionWeakness

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is CVE-2021-43535?

CVE-2021-43535 is a vulnerability that could lead to memory corruption and a potentially exploitable crash in Firefox, Thunderbird, and Firefox ESR.

2

Which software is affected by CVE-2021-43535?

Firefox versions earlier than 93, Thunderbird versions earlier than 91.3, and Firefox ESR versions earlier than 91.3 are affected by CVE-2021-43535.

3

What is the severity of CVE-2021-43535?

The severity of CVE-2021-43535 is high with a severity value of 7.

4

How can I fix CVE-2021-43535 in Firefox?

To fix CVE-2021-43535 in Firefox, update your browser to version 93 or later.

5

How can I fix CVE-2021-43535 in Thunderbird or Firefox ESR?

To fix CVE-2021-43535 in Thunderbird or Firefox ESR, update your software to version 91.3 or later.

Contact

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