CVE-2018-12373: Infoleak

Published Jul 3, 2018
·
Updated

A flaw was found in Mozilla Thunderbird before version 52.9. Decrypted S/MIME parts hidden with CSS or <plaintext> can leak plaintext when included in a HTML reply/forward.

References: https://www.mozilla.org/en-US/security/advisories/mfsa2018-18/#CVE-2018-12373 https://bugzilla.mozilla.org/showbug.cgi?id=1464667

Other sources

dDecrypted S/MIME parts hidden with CSS or <plaintext> can leak plaintext when included in a HTML reply/forward.

dDecrypted S/MIME parts hidden with CSS or the plaintext HTML tag can leak plaintext when included in a HTML reply/forward. This vulnerability affects Thunderbird < 52.9.

Launchpad

Affected Software

20 affected componentsFixes available
redhat/thunderbird<52.9
52.9
Mozilla Thunderbird<52.9
52.9
Mozilla Thunderbird<52.9.0
redhat Enterprise Linux=6.0
redhat Enterprise Linux=7.0
redhat Enterprise Linux=7.5
redhat Enterprise Linux=7.6
redhat Enterprise Linux Desktop=6.0
redhat Enterprise Linux Desktop=7.0
redhat Enterprise Linux Server=6.0
redhat Enterprise Linux Server=7.0
redhat Enterprise Linux Workstation=6.0
redhat Enterprise Linux Workstation=7.0
Debian Debian Linux=8.0
Debian Debian Linux=9.0
Canonical Ubuntu Linux=14.04
Canonical Ubuntu Linux=16.04
Canonical Ubuntu Linux=17.10
Canonical Ubuntu Linux=18.04
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

Jul 3, 2018
CVE Published
12:00 AM
Oct 18, 2018
CVE Published
via MITRE·01:00 PM
Data Sourced
via MITRE·01:00 PM
DescriptionWeakness
Jan 11, 2024
Data Sourced
via Launchpad·10:48 PM
Description
Feb 20, 2026
Data Sourced
via Ubuntu·04:28 PM
RemedyDescriptionSeverityAffected Software
Data Sourced
via Debian·04:28 PM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the severity of CVE-2018-12373?

CVE-2018-12373 has been classified as a moderate severity vulnerability.

2

How do I fix CVE-2018-12373?

To fix CVE-2018-12373, update Mozilla Thunderbird to version 52.9 or later.

3

What types of data are affected by CVE-2018-12373?

CVE-2018-12373 can leak plaintext data from decrypted S/MIME parts that are hidden with CSS or <plaintext>.

4

Which versions of Thunderbird are vulnerable to CVE-2018-12373?

Mozilla Thunderbird versions prior to 52.9 are vulnerable to CVE-2018-12373.

5

Is CVE-2018-12373 specific to a particular operating system?

CVE-2018-12373 affects the Thunderbird application regardless of the operating system it is installed on.

Contact

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