What’s Vulnerable › Vulnerabilities

CVE-2018-18493

• Severity: critical (CVSS 9.8 v3.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 5.0% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2019-02-28 · updated 2026-06-17
• Weakness: CWE-119

Description

A buffer overflow can occur in the Skia library during buffer offset calculations with hardware accelerated canvas 2D actions due to the use of 32-bit calculations instead of 64-bit. This results in a potentially exploitable crash. This vulnerability affects Thunderbird < 60.4, Firefox ESR < 60.4, and Firefox < 64.

Affected products

• Canonical Ubuntu Linux: 14.04, 16.04, 18.04, 18.10
• Debian Linux: 8.0, 9.0
• Mozilla Firefox: before 60.4.0; before 64.0 — fixed in 60.4.0, 64.0
• Mozilla Thunderbird: before 60.4.0 — fixed in 60.4.0
• 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: 7.6
• 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 60.4.0, 64.0; Mozilla Thunderbird 60.4.0. Check the vendor advisory for mitigations.

References

• http://www.securityfocus.com/bid/106168
• https://access.redhat.com/errata/RHSA-2018:3831
• https://access.redhat.com/errata/RHSA-2018:3833
• https://access.redhat.com/errata/RHSA-2019:0159
• https://access.redhat.com/errata/RHSA-2019:0160
• https://bugzilla.mozilla.org/show_bug.cgi?id=1504452
• https://lists.debian.org/debian-lts-announce/2018/12/msg00002.html
• https://security.gentoo.org/glsa/201903-04
• https://usn.ubuntu.com/3844-1/
• https://usn.ubuntu.com/3868-1/
• https://www.debian.org/security/2018/dsa-4354
• https://www.debian.org/security/2019/dsa-4362

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