What’s Vulnerable › Vulnerabilities

CVE-2017-5402

• Severity: critical (CVSS 9.8 v3.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 2.8% 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-416

Description

A use-after-free can occur when events are fired for a "FontFace" object after the object has been already been destroyed while working with fonts. This results in a potentially exploitable crash. This vulnerability affects Firefox < 52, Firefox ESR < 45.8, Thunderbird < 52, and Thunderbird < 45.8.

Affected products

• Debian Linux: 9.0
• Mozilla Firefox: before 52.0; before 45.8.0 — fixed in 45.8.0, 52.0
• Mozilla Thunderbird: before 45.8.0 — fixed in 45.8.0
• Red Hat Enterprise Linux: 5.0, 6.0, 7.0
• RedHat Enterprise Linux Desktop: 5.0, 6.0, 7.0
• RedHat Enterprise Linux Server: 5.0, 6.0, 7.0
• RedHat Enterprise Linux Server Aus: 7.3, 7.4
• RedHat Enterprise Linux Server Eus: 7.3, 7.4, 7.5
• RedHat Enterprise Linux Workstation: 5.0, 6.0, 7.0

How to fix

Upgrade to a fixed version: Mozilla Firefox 45.8.0, 52.0; Mozilla Thunderbird 45.8.0. Check the vendor advisory for mitigations.

References

• http://rhn.redhat.com/errata/RHSA-2017-0459.html
• http://rhn.redhat.com/errata/RHSA-2017-0461.html
• http://rhn.redhat.com/errata/RHSA-2017-0498.html
• http://www.securityfocus.com/bid/96664
• http://www.securitytracker.com/id/1037966
• https://bugzilla.mozilla.org/show_bug.cgi?id=1334876
• https://security.gentoo.org/glsa/201705-06
• https://security.gentoo.org/glsa/201705-07
• https://www.debian.org/security/2017/dsa-3805
• https://www.debian.org/security/2017/dsa-3832
• https://www.mozilla.org/security/advisories/mfsa2017-05/
• https://www.mozilla.org/security/advisories/mfsa2017-06/

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