CVE-2018-12393: Integer Overflow

Published Oct 23, 2018
·
Updated

A potential vulnerability was found in 32-bit builds where an integer overflow during the conversion of scripts to an internal UTF-16 representation could result in allocating a buffer too small for the conversion. This leads to a possible out-of-bounds write.

Note: 64-bit builds are not vulnerable to this issue.

External Reference:

https://www.mozilla.org/en-US/security/advisories/mfsa2018-27/#CVE-2018-12393

Other sources

A potential vulnerability was found in 32-bit builds where an integer overflow during the conversion of scripts to an internal UTF-16 representation could result in allocating a buffer too small for the conversion. This leads to a possible out-of-bounds write. Note: 64-bit builds are not vulnerable to this issue.. This vulnerability affects Firefox < 63, Firefox ESR < 60.3, and Thunderbird < 60.3.

Launchpad

A potential vulnerability was found in 32-bit builds where an integer overflow during the conversion of scripts to an internal UTF-16 representation could result in allocating a buffer too small for the conversion. This leads to a possible out-of-bounds write. Note: 64-bit builds are not vulnerable to this issue.

Mozilla

Affected Software

24 affected componentsFixes available
Mozilla Thunderbird<60.3
60.3
Mozilla Firefox<63
63
Mozilla Firefox ESR<60.3
60.3
Mozilla Firefox<63.0
Mozilla Firefox ESR<60.3
Mozilla Thunderbird<60.3
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
Canonical Ubuntu Linux=18.10
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=7.6
redhat Enterprise Linux Server Tus=7.6
redhat Enterprise Linux Workstation=6.0
redhat Enterprise Linux Workstation=7.0
debian/firefox
149.0.2-1
debian/firefox-esr
115.14.0esr-1~deb11u1140.9.1esr-1~deb11u1128.14.0esr-1~deb12u1140.9.1esr-1~deb12u1140.8.0esr-1~deb13u1140.9.1esr-1~deb13u1140.9.1esr-1
debian/thunderbird
1:115.12.0-1~deb11u11:140.9.1esr-1~deb11u11:140.6.0esr-1~deb12u11:140.9.1esr-1~deb12u11:140.8.0esr-1~deb13u11:140.9.1esr-1~deb13u11:140.9.0esr-11:140.9.1esr-1

Event History

Oct 23, 2018
CVE Published
via Mozilla·12:00 AM
Data Sourced
via Red Hat·10:07 PM
DescriptionSeverityAffected Software
Feb 28, 2019
CVE Published
via MITRE·06:00 PM
Data Sourced
via MITRE·06:00 PM
DescriptionWeakness
Jan 11, 2024
Data Sourced
via Launchpad·10:48 PM
Description
Nov 26, 2025
Data Sourced
via Ubuntu·06:15 PM
RemedyDescriptionSeverityAffected Software
Apr 15, 2026
Data Sourced
via Debian·05:01 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-2018-12393?

CVE-2018-12393 has a severity rating classified as moderate, indicating potential impact but requiring specific conditions to exploit.

2

How do I fix CVE-2018-12393?

To fix CVE-2018-12393, upgrade to the latest versions of affected software such as Mozilla Firefox ESR beyond 60.3 or Mozilla Thunderbird beyond 60.3.

3

Which versions are affected by CVE-2018-12393?

CVE-2018-12393 affects 32-bit builds of Mozilla Firefox versions up to 63 and Mozilla Thunderbird versions up to 60.3.

4

Can CVE-2018-12393 be exploited remotely?

Yes, CVE-2018-12393 can potentially be exploited remotely through malicious scripts that trigger the integer overflow.

5

What platforms are impacted by CVE-2018-12393?

CVE-2018-12393 impacts various platforms including Windows and Linux distributions using affected versions of Mozilla Firefox and Thunderbird.

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