CVE-2018-12383: Medium severity Mozilla Thunderbird vulnerability

Published Sep 5, 2018
·
Updated

If a user saved passwords before Firefox 58 and then later set a master password, an unencrypted copy of these passwords is still accessible. This is because the older stored password file was not deleted when the data was copied to a new format starting in Firefox 58. The new master password is added only on the new file. This could allow the exposure of stored password data outside of user expectations.

Affected Software

24 affected componentsFixes available
Mozilla Thunderbird<60.2.1
60.2.1
Mozilla Firefox<62
62
Mozilla Firefox ESR<60.2.1
60.2.1
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 Server Aus=7.6
redhat Enterprise Linux Server Eus=7.5
redhat Enterprise Linux Server Eus=7.6
redhat Enterprise Linux Server Tus=7.6
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=18.04
Mozilla Firefox<62.0
Mozilla Firefox ESR<60.2.1
Mozilla Thunderbird<60.2.1
debian/firefox
147.0.4-1
debian/firefox-esr
115.14.0esr-1~deb11u1140.7.0esr-1~deb11u1128.14.0esr-1~deb12u1140.7.0esr-1~deb12u1140.4.0esr-1~deb13u1140.7.0esr-1~deb13u1140.7.0esr-1
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 5, 2018
CVE Published
12:00 AM
Data Sourced
via Red Hat·07:15 AM
DescriptionSeverityAffected Software
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·10:49 PM
Description
Nov 29, 2025
Data Sourced
via Ubuntu·06:16 PM
RemedyDescriptionSeverityAffected Software
Feb 20, 2026
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-2018-12383?

The severity of CVE-2018-12383 is classified as medium.

2

How do I fix CVE-2018-12383?

To fix CVE-2018-12383, users should update to Firefox 62 or later, or replace older installations of Thunderbird and Firefox ESR with versions 60.2.1 and above.

3

What software is affected by CVE-2018-12383?

CVE-2018-12383 affects Mozilla Firefox versions prior to 62, Thunderbird versions prior to 60.2.1, and Firefox ESR versions prior to 60.2.1.

4

Can I still access my passwords after setting a master password with CVE-2018-12383?

Yes, an unencrypted copy of previously saved passwords can still be accessed even after setting a master password due to this vulnerability.

5

Is it safe to continue using affected versions of Firefox and Thunderbird in light of CVE-2018-12383?

No, it is not safe to continue using affected versions as they expose saved passwords to potential unauthorized access.

Contact

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