CVE-2019-11755: High severity Mozilla Thunderbird vulnerability

Published Sep 25, 2019
·
Updated

A crafted S/MIME message consisting of an inner encryption layer and an outer SignedData layer was shown as having a valid digital signature, although the signer might have had no access to the contents of the encrypted message, and might have stripped a different signature from the encrypted message. Previous versions had only suppressed showing a digital signature for messages with an outer multipart/signed layer.

Affected Software

3 affected componentsFixes available
Mozilla Thunderbird<68.1.1
68.1.1
Mozilla Thunderbird<68.1.1
debian/thunderbird
1:115.12.0-1~deb11u11:140.8.0esr-1~deb11u11:140.6.0esr-1~deb12u11:140.8.0esr-1~deb12u11:140.6.0esr-1~deb13u11:140.8.0esr-1~deb13u11:140.8.0esr-1

Event History

Sep 25, 2019
CVE Published
12:00 AM
Sep 27, 2019
CVE Published
via MITRE·05:10 PM
Data Sourced
via MITRE·05:10 PM
DescriptionWeakness
Jan 11, 2024
Data Sourced
via Launchpad·11:14 PM
Description
Feb 20, 2026
Data Sourced
via Ubuntu·08:34 PM
RemedyDescriptionSeverityAffected Software
Mar 5, 2026
Data Sourced
via Debian·08:45 PM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

Frequently Asked Questions

1

What is CVE-2019-11755?

CVE-2019-11755 is a vulnerability in S/MIME where a crafted message with an encryption layer and a SignedData layer may show a valid digital signature despite the signer not having access to the encrypted message.

2

Which software is affected by CVE-2019-11755?

Mozilla Thunderbird versions up to 68.1.1 and some versions of Thunderbird in Debian and Ubuntu are affected.

3

What is the severity of CVE-2019-11755?

The severity of CVE-2019-11755 is high with a CVSS score of 7.5.

4

How can I fix CVE-2019-11755?

Update Mozilla Thunderbird to version 68.2.1 or later, or follow the recommended package updates for Debian and Ubuntu.

5

Where can I find more information about CVE-2019-11755?

You can find more information about CVE-2019-11755 in the references provided: [Mozilla Bugzilla](https://bugzilla.mozilla.org/show_bug.cgi?id=1240290), [Mozilla Security Advisories](https://www.mozilla.org/en-US/security/advisories/mfsa2019-32/), [CVE Mitre](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-11755).

Contact

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