CVE-2018-5187: Buffer Overflow

Published Jun 26, 2018
·
Updated

Last updated 25 August 2025

Other sources

Memory safety bugs present in Firefox 60 and Firefox ESR 60. Some of these bugs showed evidence of memory corruption and we presume that with enough effort that some of these could be exploited to run arbitrary code. This vulnerability affects Thunderbird < 60, Firefox ESR < 60.1, and Firefox < 61.

Launchpad

Mozilla developers and community members Christian Holler, Sebastian Hengst, Nils Ohlmeier, Jon Coppeard, Randell Jesup, Ted Campbell, Gary Kwong, and Jean-Yves Avenard reported memory safety bugs present in Firefox 60 and Firefox ESR 60. Some of these bugs showed evidence of memory corruption and we presume that with enough effort that some of these could be exploited to run arbitrary code.

Affected Software

15 affected componentsFixes available
Mozilla Thunderbird<60
60
Mozilla Firefox<61
61
Mozilla Firefox ESR<60.1
60.1
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
Mozilla Firefox<61.0
Mozilla Firefox ESR<60.1.0
Mozilla Thunderbird<60.0
Mozilla Firefox<60.1.0
debian/firefox
147.0.4-1
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

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 60
  2. Upgrade

    Upgrade Firefox to a version that resolves this vulnerability.

    Fixed in 61
  3. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 60.1
  4. Upgrade

    Upgrade debian/firefox to a version that resolves this vulnerability.

    Fixed in 147.0.4-1
  5. Upgrade

    Upgrade debian/thunderbird to a version that resolves this vulnerability.

    Fixed in 1:115.12.0-1~deb11u1Fixed in 1:140.7.1esr-1~deb11u1Fixed in 1:140.6.0esr-1~deb12u1Fixed in 1:140.7.1esr-1~deb12u1Fixed in 1:140.6.0esr-1~deb13u1Fixed in 1:140.7.1esr-1~deb13u1Fixed in 1:140.7.1esr-1
  6. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 60
  7. Upgrade

    Upgrade Firefox to a version that resolves this vulnerability.

    Fixed in 60.1

Event History

Jun 26, 2018
CVE Published
via Mozilla·12:00 AM
Aug 23, 2018
Data Sourced
via Mozilla·12:00 AM
DescriptionSeverityAffected Software
Oct 18, 2018
CVE Published
via MITRE·01:00 PM
Data Sourced
via MITRE·01:00 PM
DescriptionWeakness
Data Sourced
via NVD·01:29 PM
DescriptionSeverityWeaknessAffected Software
Jan 11, 2024
Data Sourced
via Launchpad·11:06 PM
Description
Nov 25, 2025
Data Sourced
via Ubuntu·06:14 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-2018-5187?

CVE-2018-5187 has a high severity due to its potential to allow arbitrary code execution through memory safety vulnerabilities in affected applications.

2

How do I fix CVE-2018-5187?

To fix CVE-2018-5187, update affected software to the latest version, specifically Thunderbird version 60 or later and Firefox version 61 or later.

3

Which versions are affected by CVE-2018-5187?

CVE-2018-5187 affects Thunderbird versions prior to 60, Firefox ESR versions before 60.1, and Firefox versions prior to 61.

4

What products are impacted by CVE-2018-5187?

CVE-2018-5187 impacts Mozilla Thunderbird and Mozilla Firefox, specifically versions that are less than the specified fixed versions.

5

What are the potential exploits of CVE-2018-5187?

CVE-2018-5187 may be exploited to run arbitrary code due to the identified memory safety bugs if sufficient effort is applied by an attacker.

Contact

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