CVE-2021-23999: High severity thunderbird vulnerability

Published Apr 19, 2021
·
Updated

If a Blob URL was loaded through some unusual user interaction, it could have been loaded by the System Principal and granted additional privileges that should not be granted to web content.

Affected Software

9 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-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<78.10
78.10
Mozilla Firefox<88.0
Mozilla Firefox ESR<78.10
Mozilla Thunderbird<78.10
Mozilla Firefox<88
88
Mozilla Firefox ESR<78.10
78.10

Event History

Apr 19, 2021
CVE Published
via Mozilla·12:00 AM
Jun 24, 2021
CVE Published
via MITRE·01:25 PM
Data Sourced
via MITRE·01:25 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-2021-23999?

CVE-2021-23999 is classified as a moderate severity vulnerability.

2

How do I fix CVE-2021-23999?

To remediate CVE-2021-23999, users should upgrade to Mozilla Thunderbird version 78.10 or newer, or Firefox version 88 or newer.

3

What products are affected by CVE-2021-23999?

CVE-2021-23999 affects Mozilla Thunderbird versions prior to 78.10 and Mozilla Firefox ESR versions prior to 78.10.

4

What type of vulnerability is CVE-2021-23999?

CVE-2021-23999 involves improper handling of Blob URLs, which could lead to privilege escalation.

5

Is there a known exploit for CVE-2021-23999?

There are no publicly known exploits for CVE-2021-23999, but it poses a risk due to its potential impact on user privacy and security.

Contact

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