CVE-2021-38498: Use After Free

Published Oct 5, 2021
·
Updated

During process shutdown, a document could have caused a use-after-free of a languages service object, leading to memory corruption and a potentially exploitable crash.

Affected Software

6 affected componentsFixes available
Mozilla Thunderbird<91.2
91.2
Mozilla Firefox<93.0
Mozilla Firefox ESR<91.2
Mozilla Thunderbird<91.2
Mozilla Firefox<93
93
Mozilla Firefox ESR<91.2
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

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is CVE-2021-38498?

CVE-2021-38498 is a vulnerability in Mozilla Thunderbird and Firefox that can cause a use-after-free of a languages service object, leading to memory corruption and a potentially exploitable crash.

2

How severe is CVE-2021-38498?

CVE-2021-38498 has a severity rating of medium.

3

Which software versions are affected by CVE-2021-38498?

CVE-2021-38498 affects Mozilla Thunderbird up to version 91.2, Firefox ESR up to version 91.2, and Firefox up to version 93.

4

How can I fix CVE-2021-38498?

To fix CVE-2021-38498, update Mozilla Thunderbird to version 91.2, Firefox ESR to version 91.2, or Firefox to version 93.

5

Where can I find more information about CVE-2021-38498?

You can find more information about CVE-2021-38498 in the following references: [Mozilla Bugzilla](https://bugzilla.mozilla.org/show_bug.cgi?id=1729642), [Mozilla Security Advisory MFSAs](https://www.mozilla.org/en-US/security/advisories/mfsa2021-47/), [Mozilla Security Advisory MFSA2021-43](https://www.mozilla.org/en-US/security/advisories/mfsa2021-43/).

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