CVE-2021-38496: Use After Free

Published Oct 5, 2021
·
Updated

During operations on MessageTasks, a task may have been removed while it was still scheduled, resulting in memory corruption and a potentially exploitable crash.

Affected Software

16 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<91.2
91.2
Mozilla Firefox<93
93
Mozilla Firefox ESR<91.2
91.2
Mozilla Firefox ESR<78.15
78.15
Mozilla Firefox<93.0
Mozilla Firefox>=91.0<91.2
Mozilla Firefox ESR<78.15
Mozilla Thunderbird<78.15
Mozilla Thunderbird>=91.0<91.2
Debian Debian Linux=9.0
Debian Debian Linux=10.0
Debian Debian Linux=11.0
Mozilla Firefox ESR>=91.0<91.2

Event History

Oct 5, 2021
CVE Published
via Mozilla·12:00 AM
Nov 3, 2021
CVE Published
via MITRE·12:03 AM
Data Sourced
via MITRE·12:03 AM
DescriptionWeakness
Data Sourced
via NVD·01:15 AM
DescriptionSeverityWeaknessAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is CVE-2021-38496?

CVE-2021-38496 is a vulnerability that may result in memory corruption and a potentially exploitable crash in Thunderbird and Firefox.

2

Which software versions are affected by CVE-2021-38496?

CVE-2021-38496 affects Thunderbird < 78.15, Thunderbird < 91.2, Firefox ESR < 91.2, Firefox ESR < 78.15, and Firefox < 93.

3

What is the severity of CVE-2021-38496?

CVE-2021-38496 has a severity rating of 8.8 (high).

4

How can I fix CVE-2021-38496?

To fix CVE-2021-38496, it is recommended to update Thunderbird and Firefox to the latest available versions.

5

Where can I find more information about CVE-2021-38496?

You can find more information about CVE-2021-38496 on the Mozilla Bugzilla and Mozilla Security Advisories websites, as well as the Debian LTS Announce mailing list.

Contact

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