CVE-2019-11739: Medium severity Mozilla Thunderbird vulnerability

Published Sep 6, 2019
·
Updated

Encrypted S/MIME parts in a crafted multipart/alternative message can leak plaintext when included in a a HTML reply/forward.

Affected Software

5 affected componentsFixes available
Mozilla Thunderbird<60.9
60.9
Mozilla Thunderbird<68.1
68.1
Mozilla Thunderbird<60.9.0
Mozilla Thunderbird>=68.0<68.1.0
debian/thunderbird
1:115.12.0-1~deb11u11:140.7.1esr-1~deb11u11:140.6.0esr-1~deb12u11:140.7.1esr-1~deb12u11:140.6.0esr-1~deb13u11:140.7.1esr-1~deb13u11:140.7.1esr-1

Event History

Sep 6, 2019
CVE Published
12:00 AM
Sep 27, 2019
CVE Published
via MITRE·05:19 PM
Data Sourced
via MITRE·05:19 PM
DescriptionWeakness
Data Sourced
via NVD·06:15 PM
DescriptionSeverityWeaknessAffected Software
Aug 8, 2024
Data Sourced
via Launchpad·11:13 PM
Description
Dec 4, 2025
Data Sourced
via Ubuntu·06:19 PM
RemedyDescriptionSeverityAffected Software
Feb 20, 2026
Data Sourced
via Debian·10:30 PM
DescriptionAffected Software

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 CVE-2019-11739?

CVE-2019-11739 is a vulnerability in Mozilla Thunderbird that allows encrypted S/MIME parts in a crafted multipart/alternative message to leak plaintext when included in a HTML reply or forward.

2

How does CVE-2019-11739 affect Thunderbird?

CVE-2019-11739 affects Thunderbird versions 60.9 up to but not including 68.1.

3

What is the severity of CVE-2019-11739?

CVE-2019-11739 has a severity value of 7, which is considered high.

4

How can I fix CVE-2019-11739?

To fix CVE-2019-11739, update Thunderbird to version 60.9 or higher, but not including version 68.1.

5

Where can I find more information about CVE-2019-11739?

You can find more information about CVE-2019-11739 in the following references: [Mozilla Bugzilla](https://bugzilla.mozilla.org/show_bug.cgi?id=1571481), [Mozilla Security Advisories](https://www.mozilla.org/en-US/security/advisories/mfsa2019-30/) and [Mozilla Security Advisories](https://www.mozilla.org/en-US/security/advisories/mfsa2019-29/).

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