CVE-2021-38504: Use After Free

Published Nov 2, 2021
·
Updated

When interacting with an HTML input element's file picker dialog with webkitdirectory set, a use-after-free could have resulted, leading to memory corruption and a potentially exploitable crash.

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<94
94
Mozilla Firefox ESR<91.3
91.3
Mozilla Firefox<94.0
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

Nov 2, 2021
CVE Published
12:00 AM
Dec 8, 2021
CVE Published
via MITRE·09:21 PM
Data Sourced
via MITRE·09:21 PM
DescriptionWeakness

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the severity of CVE-2021-38504?

The severity of CVE-2021-38504 is high with a CVSS score of 8.8.

2

Which software is affected by CVE-2021-38504?

CVE-2021-38504 affects Firefox versions less than 94, Thunderbird versions less than 91.3, and Firefox ESR versions less than 91.3.

3

How can I fix CVE-2021-38504?

To fix CVE-2021-38504, update to Firefox version 94 or later, Thunderbird version 91.3 or later, or Firefox ESR version 91.3 or later.

4

What is the description of CVE-2021-38504?

CVE-2021-38504 is a vulnerability that could lead to memory corruption and a potentially exploitable crash when interacting with an HTML input element's file picker dialog with webkitdirectory set.

5

Where can I find more information about CVE-2021-38504?

You can find more information about CVE-2021-38504 in the following references: [Bugzilla](https://bugzilla.mozilla.org/show_bug.cgi?id=1730156), [Mozilla Security Advisory](https://www.mozilla.org/en-US/security/advisories/mfsa2021-49/), [Debian LTS Announce](https://lists.debian.org/debian-lts-announce/2021/12/msg00030.html).

Contact

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