CVE-2021-38503: Critical severity thunderbird vulnerability

Published Nov 2, 2021
·
Updated

The iframe sandbox rules were not correctly applied to XSLT stylesheets, allowing an iframe to bypass restrictions such as executing scripts or navigating the top-level frame.

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
Mozilla Thunderbird<91.3
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·09:22 PM
Data Sourced
via MITRE·09:22 PM
DescriptionWeakness

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the CVE ID for this vulnerability?

The CVE ID for this vulnerability is CVE-2021-38503.

2

Which software products are affected by this vulnerability?

This vulnerability affects Firefox versions earlier than 94, Thunderbird versions earlier than 91.3, and Firefox ESR versions earlier than 91.3.

3

What is the severity of CVE-2021-38503?

CVE-2021-38503 has a severity rating of critical.

4

How can I fix this vulnerability?

To fix this vulnerability, update your Firefox to version 94 or later, Thunderbird to version 91.3 or later, or Firefox ESR to version 91.3 or later.

5

Where can I find more information about CVE-2021-38503?

You can find more information about CVE-2021-38503 in the following references: [link1], [link2], [link3].

Contact

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