What’s Vulnerable › Vulnerabilities

CVE-2018-5178

• Severity: high (CVSS 8.1 v3.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 4.9% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2018-06-11 · updated 2026-06-17
• Weakness: CWE-119

Description

A buffer overflow was found during UTF8 to Unicode string conversion within JavaScript with extremely large amounts of data. This vulnerability requires the use of a malicious or vulnerable legacy extension in order to occur. This vulnerability affects Thunderbird ESR < 52.8, Thunderbird < 52.8, and Firefox ESR < 52.8.

Affected products

• Canonical Ubuntu Linux: 14.04, 16.04, 17.10, 18.04
• Debian Linux: 7.0, 8.0, 9.0
• Mozilla Firefox: before 52.8.0 — fixed in 52.8.0
• Mozilla Thunderbird: before 52.8.0 — fixed in 52.8.0
• Mozilla Thunderbird ESR: before 52.8.0 — fixed in 52.8.0
• RedHat Enterprise Linux Desktop: 6.0, 7.0
• RedHat Enterprise Linux Server: 6.0, 7.0
• RedHat Enterprise Linux Server Aus: 7.6
• RedHat Enterprise Linux Server Eus: 7.5, 7.6
• RedHat Enterprise Linux Server Tus: 7.6
• RedHat Enterprise Linux Workstation: 6.0, 7.0

How to fix

Upgrade to a fixed version: Mozilla Firefox 52.8.0; Mozilla Thunderbird 52.8.0; Mozilla Thunderbird ESR 52.8.0. Check the vendor advisory for mitigations.

References

• http://www.securityfocus.com/bid/104138
• http://www.securitytracker.com/id/1040898
• https://access.redhat.com/errata/RHSA-2018:1414
• https://access.redhat.com/errata/RHSA-2018:1415
• https://access.redhat.com/errata/RHSA-2018:1725
• https://access.redhat.com/errata/RHSA-2018:1726
• https://bugzilla.mozilla.org/show_bug.cgi?id=1443891
• https://lists.debian.org/debian-lts-announce/2018/05/msg00007.html
• https://lists.debian.org/debian-lts-announce/2018/05/msg00013.html
• https://security.gentoo.org/glsa/201810-01
• https://security.gentoo.org/glsa/201811-13
• https://usn.ubuntu.com/3660-1/

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