CVE-2021-29969: Medium severity thunderbird vulnerability

Published Jul 13, 2021
·
Updated

If Thunderbird was configured to use STARTTLS for an IMAP connection, and an attacker injected IMAP server responses prior to the completion of the STARTTLS handshake, then Thunderbird didn't ignore the injected data. This could have resulted in Thunderbird showing incorrect information, for example the attacker could have tricked Thunderbird to show folders that didn't exist on the IMAP server.

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<78.12
78.12
Mozilla Thunderbird<78.12

Event History

Jul 13, 2021
CVE Published
12:00 AM
Aug 5, 2021
CVE Published
via MITRE·07:46 PM
Data Sourced
via MITRE·07:46 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-2021-29969?

CVE-2021-29969 has a moderate severity level due to the potential for attackers to inject misleading data.

2

How do I fix CVE-2021-29969?

To fix CVE-2021-29969, users should upgrade Thunderbird to version 78.12 or later.

3

What versions of Thunderbird are affected by CVE-2021-29969?

CVE-2021-29969 affects Thunderbird versions prior to 78.12.

4

What impact does CVE-2021-29969 have on Thunderbird users?

CVE-2021-29969 may cause Thunderbird to display incorrect information due to injected IMAP server responses.

5

Is there a workaround for CVE-2021-29969?

There is no specific workaround for CVE-2021-29969; users are advised to update Thunderbird to the latest version.

Contact

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