CVE-2021-4140: Critical severity thunderbird vulnerability

Published Jan 11, 2022
·
Updated

It was possible to construct specific XSLT markup that would be able to bypass an iframe sandbox.

Affected Software

6 affected componentsFixes available
Mozilla Thunderbird<91.5
91.5
Mozilla Firefox<96.0
Mozilla Firefox ESR<91.5
Mozilla Thunderbird<91.5
Mozilla Firefox<96
96
Mozilla Firefox ESR<91.5
91.5

Event History

Jan 11, 2022
CVE Published
via Mozilla·12:00 AM
Dec 22, 2022
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
DescriptionWeakness
Data Sourced
via NVD·08:15 PM
RemedyDescriptionSeverityWeaknessAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is the vulnerability ID of this issue?

The vulnerability ID of this issue is CVE-2021-4140.

2

What is the severity of CVE-2021-4140?

The severity of CVE-2021-4140 is critical.

3

Which software versions are affected by CVE-2021-4140?

CVE-2021-4140 affects Firefox ESR versions before 91.5, Firefox versions before 96, and Thunderbird versions before 91.5.

4

How can an attacker exploit CVE-2021-4140?

An attacker can exploit CVE-2021-4140 by constructing specific XSLT markup to bypass an iframe sandbox.

5

Where can I find more information about CVE-2021-4140?

You can find more information about CVE-2021-4140 in the following references: [Mozilla Bugzilla](https://bugzilla.mozilla.org/show_bug.cgi?id=1746720), [Mozilla Security Advisory MFSA2022-03](https://www.mozilla.org/en-US/security/advisories/mfsa2022-03/), [Mozilla Security Advisory MFSA2022-01](https://www.mozilla.org/en-US/security/advisories/mfsa2022-01/).

Contact

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