CVE-2021-23993: Medium severity thunderbird vulnerability

Published Apr 8, 2021
·
Updated

An attacker may perform a DoS attack to prevent a user from sending encrypted email to a correspondent. If an attacker creates a crafted OpenPGP key with a subkey that has an invalid self signature, and the Thunderbird user imports the crafted key, then Thunderbird may try to use the invalid subkey, but the RNP library rejects it from being used, causing encryption to fail.

Affected Software

3 affected componentsFixes available
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<78.9.1
78.9.1
Mozilla Thunderbird<78.9.1

Event History

Apr 8, 2021
CVE Published
12:00 AM
Jun 24, 2021
CVE Published
via MITRE·01:26 PM
Data Sourced
via MITRE·01:26 PM
DescriptionWeakness

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

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Frequently Asked Questions

1

What is the severity of CVE-2021-23993?

CVE-2021-23993 has been classified as a moderate severity vulnerability.

2

How do I fix CVE-2021-23993?

To fix CVE-2021-23993, update Thunderbird to version 78.9.1 or later.

3

What type of attack does CVE-2021-23993 enable?

CVE-2021-23993 allows an attacker to perform a Denial of Service (DoS) attack.

4

Which software versions are affected by CVE-2021-23993?

CVE-2021-23993 affects Thunderbird versions prior to 78.9.1.

5

What is the impact of exploiting CVE-2021-23993?

Exploiting CVE-2021-23993 can prevent users from sending encrypted emails.

Contact

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